CN115084302B

CN115084302B - Photoelectric device based on enhanced photoelectric recycling effect, preparation method and application

Info

Publication number: CN115084302B
Application number: CN202110283726.0A
Authority: CN
Inventors: 丁贺; 盛兴; 史钊; 吕国庆
Original assignee: Tsinghua University; Beijing Institute of Technology BIT
Current assignee: Tsinghua University; Beijing Institute of Technology BIT
Priority date: 2021-03-16
Filing date: 2021-03-16
Publication date: 2024-12-13
Anticipated expiration: 2041-03-16
Also published as: CN115084302A

Abstract

The present disclosure provides a photoelectric device based on enhanced photoelectric recycling effect, comprising: a substrate; a P-type electrode layer, which is located at one end of the substrate surface; a bottom battery layer, which is located at the other end of the substrate surface to be connected to the P-type electrode layer, and the bottom battery layer is used to absorb excitation light photons and convert them into electrons to achieve photoelectric-electro-optical conversion; a highly doped tunnel junction layer, which is located on the bottom battery and is used to provide a low-resistance and optically low-loss connection; a top battery layer, which is located on the highly doped tunnel junction layer and is used to absorb excitation light photons and convert them into electrons to achieve photoelectric conversion; wherein the energy band width of the top battery layer is greater than or equal to the energy band width of the bottom battery layer; an N-type electrode layer, which is located at one end of the surface of the top battery layer. The present disclosure also provides a method for preparing a photoelectric device based on enhanced photoelectric recycling effect and its application.

Description

Photoelectric device based on photoelectric recovery effect enhancement, preparation method and application

Technical Field

The disclosure relates to the field of semiconductor photoelectric devices, in particular to a photoelectric device based on photoelectric recovery effect enhancement, a preparation method and application.

Background

Understanding and engineering optical processes in semiconductor materials is critical to achieving high performance photovoltaic devices such as Photovoltaic (PV) cells, photodetectors, light Emitting Diodes (LEDs), and lasers. In light emitting semiconductors, photon absorption, re-emission and self-absorption processes (also known as photon recycling effects) are of great interest in the study of photon receivers. In particular, remarkable results have recently been shown on III-V and halide perovskite based semiconductors, where improved photon recovery effects result in single or multi junction PV cells with ultra high power conversion efficiency. In these PV cells, the enhanced photon recovery effect increases the open circuit voltage (Voc) and photo-generated current, resulting in a more efficient conversion output for the photovoltaic device.

In general, the photon recovery effect is mainly performed under standard single day illumination of PV cells, where various strategies have been employed, such as reflector optimization and light trapping designs, to manipulate internally radiated photons. Meanwhile, the photoelectric characteristics (quantum efficiency, carrier lifetime, etc.) of semiconductor materials and devices depend on the wavelength and power of incident light, but little research is conducted on the influence of photon recycling. Particularly in multi-junction devices, the photon recycling process can affect and change the current matching conditions of the multi-junction cell.

The present disclosure is based on photon recovery processes in photovoltaic devices with enhanced photovoltaic recovery effects, and experiments and analyses study photon and carrier transport behavior at various wavelengths and intensities. In the optoelectronic device, the excitation light incident wavelength is found to affect the current matching conditions, resulting in a varying photon recovery effect. Under the illumination of purple blue (400-480 nm) and near infrared (800 nm), the dependence of the output current of the photoelectric device on the incident power is obviously different. These results indicate that the photon recovery effect plays a critical role in the design of optoelectronic devices.

Disclosure of Invention

In order to solve the above problems in the prior art, the present disclosure provides a photoelectric device based on the enhancement of the photoelectric recovery effect, a preparation method and application thereof, and by reasonably designing the structure, the preparation material and the thin film layer thickness of the photoelectric device, the internal quantum efficiency and the output voltage of the device are higher.

The first aspect of the disclosure provides an optoelectronic device based on photoelectric recovery effect enhancement, which comprises a substrate, a P-type electrode layer located at one end of the surface of the substrate, a bottom battery layer located at the other end of the surface of the substrate and connected with the P-type electrode layer, wherein the bottom battery layer is used for absorbing excitation light photons to convert electrons to realize photoelectric-electro-optical conversion, a high-doped tunnel junction layer located on the bottom battery and used for providing a connection effect with low resistance and optical low loss, a top battery layer located on the high-doped tunnel junction layer and used for absorbing the excitation light photons to convert electrons to realize photoelectric conversion, and an N-type electrode layer located at one end of the surface of the top battery layer.

Further, the internal quantum efficiency η _int of the optoelectronic device satisfies the following relationship:

Where R is a function related to the excess carrier density, B is a constant of 1.5×10 ^-10s^-1cm³, h ₀ is the hole density in the thermal equilibrium state of the optoelectronic device, Δh is the excess hole density of the optoelectronic device, q ₀ is the electron density in the thermal equilibrium state of the optoelectronic device, Δq is the excess electron density of the optoelectronic device, and n _i is the intrinsic carrier density.

Further, a direct current bias is applied between the P-type electrode layer and the N-type electrode layer, and the current I in the photoelectric device and the internal quantum efficiency eta _int thereof meet the following relation:

wherein I _ex is the current of the photon flux of the incident excitation light.

Further, the layer thickness of the top cell layer is smaller than the layer thickness of the bottom cell.

Further, the bottom cell layer is a GaAs cell layer or an InGaAs cell or an InP cell layer.

Further, the top cell layer is a GaP cell layer or a GaN cell layer or a GaAs cell layer.

Further, the N-type electrode layer is formed by sequentially laminating and growing Ge, ni and Au metals.

Further, the P-type electrode layer is formed by sequentially stacking and growing Cr and Au metals.

The second aspect of the disclosure provides a method for manufacturing a photoelectric device based on photoelectric recovery effect enhancement, which comprises the steps of S1, sequentially growing a bottom battery layer, a high-doped tunnel junction layer and a top battery layer on a substrate, S2, forming a P-type electrode layer on one side of the substrate by adopting evaporated metal, and S3, forming an N-type electrode layer on one side of the top battery layer by adopting evaporated metal.

A third aspect of the present disclosure provides the use of photovoltaic devices based on enhanced photovoltaic recycling effects in high performance photovoltaic devices.

Compared with the prior art, the method has the following beneficial effects:

(1) The optimized photovoltaic device provided by the present disclosure can achieve a response of optimal photovoltaic recycling effect around 800nm, such as a high efficiency near infrared photodetector.

(2) The GaAs material-based optoelectronic device provided by the present disclosure is more suitable for implementing photon recycling processes than InGaP, which has higher internal quantum efficiency.

(3) Compared with a device with a thicker material layer, the serial connection ultrathin GaAs junction provided by the disclosure has higher carrier collection efficiency and can realize high output voltage.

(4) The photovoltaic device provided by the present disclosure is a high current mismatched dual junction device that clearly exhibits high photon recovery efficiency related to excitation light input power.

(5) The bottom cell layer may be of a low band gap absorption material such as InGaAs material or InP.

Drawings

For a more complete understanding of the present disclosure and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

FIG. 1A schematically illustrates a perspective view of a photovoltaic device based on photovoltaic recycling enhancement in accordance with an embodiment of the present disclosure;

FIG. 1B schematically illustrates an effect schematic of an optoelectronic device based on enhanced photovoltaic recycling effect on glass by a transfer printing process, in accordance with an embodiment of the present disclosure;

FIG. 1C schematically illustrates an external quantum efficiency spectrum contrast plot for a top cell and a bottom cell at different input excitation light wavelengths, in accordance with an embodiment of the present disclosure;

FIG. 1D schematically illustrates an external quantum efficiency spectrum contrast plot at 850nm and 470nm saturation bias excitation light, in accordance with an embodiment of the present disclosure;

FIGS. 2A and 2B schematically illustrate optical contrast diagrams inside the optoelectronic device under illumination with incident excitation light of 475nm and 810nm, according to an embodiment of the present disclosure;

FIG. 2C schematically illustrates a comparison of photon distribution effects at different layer thicknesses for the optoelectronic device according to an embodiment of the present disclosure;

FIG. 2D schematically illustrates internal quantum efficiency versus graph for a bottom cell at different bias voltages in accordance with an embodiment of the present disclosure;

FIGS. 3A and 3B schematically illustrate PL attenuation contrast graphs of incident excitation light at different optical power densities at 800nm and 410nm, according to an embodiment of the present disclosure;

FIG. 3C schematically illustrates a plot of PL decay lifetime τ versus photon flux at 800nm and 410nm for incident excitation light according to an embodiment of the disclosure;

FIG. 3D schematically illustrates a comparison graph of internal quantum efficiencies η _int of incident excitation light at 800nm and 410nm, in accordance with an embodiment of the present disclosure;

FIGS. 4A and 4B schematically illustrate current-voltage characteristic comparisons of incident excitation light at different optical power densities of 800nm and 410nm, according to an embodiment of the present disclosure;

FIG. 4C schematically illustrates a graph of current versus excitation power at 800nm and 475nm for incident excitation light according to an embodiment of the present disclosure;

FIG. 4D schematically illustrates an external quantum efficiency spectrum contrast plot for different internal quantum efficiencies η _int of the optoelectronic device of an embodiment of the present disclosure;

FIG. 5A schematically illustrates a schematic of the response of a GaAs/InGaAs cell layer to different wavelengths in accordance with another embodiment of the present disclosure;

FIG. 5B schematically illustrates conversion response of a GaAs/InGaAs optoelectronic device to different wavelengths with different photon recycling enhancement effects in accordance with another embodiment of the present disclosure;

FIG. 6A schematically illustrates a schematic of the response of a GaAs/InP cell layer to different wavelengths in accordance with yet another embodiment of the present disclosure;

FIG. 6B schematically illustrates a schematic diagram of the conversion response of a GaAs/InGaAs optoelectronic device to different wavelengths with different photon recycling enhancement effects in accordance with yet another embodiment of the present disclosure;

Fig. 7 schematically illustrates a flow chart of the fabrication of an optoelectronic device based on enhanced photovoltaic recycling effect, in accordance with an embodiment of the present disclosure.

Detailed Description

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood that the description is only exemplary and is not intended to limit the scope of the present disclosure. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. It may be evident, however, that one or more embodiments may be practiced without these specific details. In addition, in the following description, descriptions of well-known structures and techniques are omitted so as not to unnecessarily obscure the concepts of the present disclosure.

It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. Furthermore, in the description and in the claims, when an element is described as being "connected" to another element, the element may be "directly connected" to the other element or "connected" to the other element through a third element.

As shown in fig. 1, an optoelectronic device based on enhanced photoelectric recovery effect according to an embodiment of the present disclosure includes:

and a substrate l, wherein the substrate is a GaAs substrate.

And a P-type electrode layer 2 positioned at one end of the surface of the substrate 1, wherein the P-type electrode layer 2 is formed by sequentially stacking Cr and Au metals for growth, and the thickness of the layer is 200nm.

And a bottom cell layer 3, which is located at the other end of the surface of the substrate 1 and is connected with or opposite to the P-type electrode layer 2, wherein the bottom cell layer 3 is used for absorbing excitation light photons to convert electrons, so as to realize photoelectric-electro-optical conversion.

In the embodiment of the present disclosure, the bottom cell layer 3 adopts a photoelectric structure for long wavelength absorption conversion or the same photoelectric material of the upper and lower layers with a larger thickness, such as a silicon cell or GaAs cell layer or InP cell layer. The embodiment of the disclosure takes a GaAs structure battery layer with larger thickness As an example of a bottom battery layer 3, which comprises a p-type InGaP-BSF layer, a p-type GaAs substrate, an n-type GaAs emitter and an n-type Al _0.3Ga_0.7 As window sequentially grown on the surface of the substrate, wherein the p-type InGaP-BSF layer is formed by Mg doping with a doping concentration of 1×10 ¹⁸cm^-3, the thickness of the p-type InGaP-BSF layer is 500nm, the p-type GaAs substrate is formed by Zn doping with a doping concentration of 1×10 ¹⁷cm^-3, the thickness of the p-type GaAs substrate is 450nm, the n-type GaAs emitter is formed by Si doping with a doping concentration of 2×10 ¹⁸cm^-3, the thickness of the n-type Al _0.3Ga_0.7 As window is formed by Si doping with a doping concentration of 2×10 ¹⁸cm^-3, and the thickness of the p-type GaAs substrate is 30nm.

The high doped tunnel junction layer 4 is located on the bottom cell layer 3, the high doped tunnel junction layer 4 is located between the bottom cell layer 3 and the top cell layer 5 and is used for providing a low-resistance and optical low-loss connection effect, the high doped tunnel junction layer comprises an N-type GaAs layer and a P-type GaAs layer which are sequentially located on the surface of the bottom cell layer 3, the N-type GaAs layer is an N-type GaAs layer with Se doping concentration of 9×10 ¹⁹cm^-3, the thickness of the N-type GaAs layer is 11nm, the P-type GaAs layer is a P-type GaAs layer with C doping concentration of 8×10 ¹⁹cm^-3, and the thickness of the P-type GaAs layer is 11nm.

And the top cell layer 5 is positioned on the high-doped tunnel junction layer 4, wherein the energy band width of the top cell layer 5 is larger than or equal to that of the bottom cell layer 3, and the top cell layer is used for absorbing excitation light photons to convert the excitation light photons into electrons so as to realize photoelectric conversion. In the embodiment of the present disclosure, the top cell layer 5 is made of an optoelectronic structure for short wavelength or the same optoelectronic material with a smaller thickness, such as a GaP cell layer or a GaN cell layer or a GaAs cell layer, which can realize "optoelectronic/electro-optical". Taking a GaAs structure battery layer with a thinner thickness As an example of the top battery layer 5, the embodiment of the disclosure includes a P-type Al _0.3Ga_0.7 As-BSF layer, a P-type GaAs base, an N-type GaAs emitter and an N-type InGaP window sequentially grown on the surface of the highly doped tunnel junction layer 4, the P-type Al _0.3Ga_0.7 As-BSF layer is formed by Mg doping with a doping concentration of 5×10 ¹⁸cm^-3, the thickness of the P-type Al _0.3Ga_0.7 As-BSF layer is 100nm, the P-type GaAs base is formed by Zn doping with a doping concentration of 1×10 ¹⁷cm^-3, the thickness of the P-type GaAs base is 1500nm, the N-type GaAs emitter is formed by Si doping with a doping concentration of 2×10 ¹⁸cm^-3, the thickness of the N-type InGaP window is 100nm, and the thickness of the N-type InGaP window is 30nm.

And an N-type electrode layer 6 positioned at one end of the surface of the top battery layer 5, wherein the N-type electrode layer 6 is formed by sequentially laminating and growing Ge, ni and Au metals, and the thickness of the N-type electrode layer is 200nm.

The P-type electrode layer 2 and the N-type electrode layer 6 are used for forming good ohmic contact with an external circuit.

Fig. 1B schematically illustrates an effect schematic of an optoelectronic device based on enhanced photovoltaic recycling effect on glass by a transfer printing method, the optoelectronic device having dimensions of 700 μm x 700 μm and a total layer thickness of 3.8 μm, according to an embodiment of the present disclosure.

According to embodiments of the present disclosure, the External Quantum Efficiency (EQE) spectra of the top and bottom cell layers 5, 3 at different input excitation light wavelengths are calculated using a finite element method, as shown in fig. 1C, such that the photovoltaic device achieves a maximum EQE at about 800nm, with the top and bottom cell layers 5, 3 absorbing an equivalent amount of photons and achieving current matching between the two cell layers, and at other incident excitation light wavelengths, the total current of the photovoltaic device is determined by the subcells with smaller current output due to their deviations from the current matching conditions, and thus the total EQE of the photovoltaic device is reduced compared to the EQE of the top and bottom cell layers 5, 3.

According to the embodiment of the disclosure, the photoelectric device is input with 850nm and 470nm saturated bias light during the experiment, the EQE of the top cell layer 5, the bottom cell layer 3 and the photoelectric device under the saturated bias light are measured, and the irradiation intensity of the monochromatic light is 1-3 mw/cm ², as shown in fig. 1D, the experimental result is mild and good as the calculation result of fig. 1C, and the thickness variation and the unnecessary carrier loss of the surface of the photoelectric device during the deposition of the epitaxial layer cause some differences.

According to an embodiment of the present disclosure, the optoelectronic device was illuminated with monochromatic light at 475nm and 810nm, respectively, during the experiment, and the EQE under illumination by different light sources was measured, respectively, as shown in fig. 2A, at 475nm, more than 99% of the photons were captured and absorbed by the top cell layer 5, which produced much more free carriers than the bottom cell. Wherein the total photocurrent generated when the top cell layer 5 is connected in series with the bottom cell layer3 and measured under short circuit conditions, i.e. v=0, is negligible so that the EQE is close to zero. As shown in fig. 2B, the 810nm infrared light is deeper into the cell layer than the 475nm illumination light, resulting in a more uniform photon distribution, which can achieve current matching and thus maximum EQE.

Those skilled in the art will appreciate that in GaAs etc. high emission materials, photons and carriers can be "recovered" by re-emission and re-absorption if not collected by an external circuit due to current mismatch, which in turn can alter the photon distribution inside the device. As shown in fig. 2A, the photogenerated electrons and holes in the top cell layer 5 are trapped and recombine by radiative and non-radiative processes, the radiation being coincident with creating re-emitted photons at the semiconductor edge, which are redistributed throughout the device, creating photocarriers in the top cell layer 5, i.e. the bottom cell layer 3, and resulting in a non-zero photocurrent, and the changing photons being dependent on the radiation efficiency of the semiconductor material, i.e. the internal quantum efficiency η _int.

According to an embodiment of the present disclosure, as shown in fig. 2C, the correspondence of photon distributions at 475nm and 870nm of different incident excitation light with different layer thicknesses of the optoelectronic device is plotted and calculated according to the beer-lambert law, when η _int =0, blue light of 475nm is irradiated, and strictly obeying the beer-lambert law, as η _int increases, photons re-emitted at 870nm need to be considered, which penetrates into a deeper region of the optoelectronic device due to the decrease of absorption coefficient of GaAs. It is known that this photon recovery process can severely impact the performance of the bottom cell. In the embodiments of the present disclosure, it is assumed that the incident power of 475nm blue illumination is 400W/m ², and the current-voltage characteristics of the top cell layer 5 and the bottom cell layer 3 in the optoelectronic device are calculated for different η _int. When the photovoltaic device is operated under a short circuit condition, the total current I and the total voltage V thereof satisfy the following relationship with the top cell layer 5 (I ₁,V₁) and the bottom cell layer 3 (I ₂,V₂):

I=I₁＝I₂,V₁+V₂=0

According to an embodiment of the present disclosure, as shown in fig. 2D, the intersection points in the graph represent the operating conditions of the photovoltaic device at 475nm for the top cell layer 5 and the bottom cell layer 3, the top cell layer 5 is set to forward bias and emit IR photons, and the bottom cell layer 3 receives recovered IR photons and operates with reverse bias, which photon-cycling effect is negligible at 810nm incident light compared to 475nm incident light, as shown in fig. 2B, because under current matching conditions the photogenerated carriers are immediately collected by external circuitry. In an embodiment of the disclosure, to experimentally verify the photo-carrier dynamics of the optoelectronic device, time-resolved photoluminescence (TRPL) measurements were performed using a femtosecond laser at different excitation wavelengths, as shown in fig. 3A and 3B, PL attenuations of the incident excitation light at different power densities of 800nm and 410nm were tested, respectively, the power density selection range was 1.4x10 ⁴W/m²～1.4×10⁷W/m² (power density increment corresponding to the bottom-up curve in fig. 3A) at 800nm, the power density selection range was 1x10 ⁵W/m²～1.4×10⁷W/m² (power density increment corresponding to the bottom-up curve in fig. 3B) at 410nm, and the PL attenuation lifetime τ obtained at two wavelengths was obtained as a function of photon flux compared to a fitted curve based on a standard ABC model, as shown in fig. 3C:

Where R represents non-radiative recombination and is a function of excess carrier density, B represents radiative recombination, Z is related to Auger recombination, which is negligible at relatively low carrier densities, q ₀ is the electron density of the optoelectronic device in its thermal equilibrium state, and Δq is the excess electron density of the optoelectronic device, assuming that B is a constant of 1.5X10 ^-10s^-1cm³. The difference between the analyzed and fitted curve and the measured data is shown in fig. 3C, and according to the relationship between the lifetime and the carrier concentration, the corresponding quantum efficiency is obtained. Modeling using the above formula is difficult due to complex non-radiative recombination mechanisms, such as surface defects, deep level traps, etc. And the internal quantum efficiency η _int may be expressed as the ratio of the radiative recombination rate C _rad to the non-radiative recombination rate C _non-rad:

Where p ₀ is the excess hole density of the photovoltaic device, Δp is the excess hole density of the photovoltaic device, and n _i is the intrinsic carrier density. According to the disclosed embodiments, based on the experimental results of τ, η _int can be calculated as a function of photon flux, as shown in fig. 3D, η _int increases monotonically with absorbed photon flux due to the gradual saturation effect of the non-radiative recombination centers.

According to the embodiment of the disclosure, the current-voltage characteristics of the incident excitation light at different optical power densities of 810nm and 475nm are tested, wherein the power density selection range is 0.02W/m ²～2.2×10⁶W/m² at 810nm and 70W/m ²～10⁶W/m² at 475 nm. As shown in fig. 4A and 4B, the open circuit voltage of the photovoltaic device is about 2V, the optical circuit increases according to the increase of the irradiation power, the measured current density is related to the excitation power under the irradiation of the 810nm and 475nm light source, as shown in fig. 4C, photons absorbed by the photovoltaic device are almost uniformly distributed in each material layer of the photovoltaic device at 810nm, as shown in fig. 1C, photon absorption rate in the top cell layer 5 and the bottom cell layer 3 is about 40%, and thus, when the photovoltaic device reaches the current matching condition, the output current is linearly proportional to the excitation power:

I=I_ex×EQE

wherein I _ex is the current of the photon flux of the incident excitation light. Conversely, most of the photons are absorbed by the top cell layer 5 under 475nm light, and only a minority of the photogenerated carriers generate re-emitted photons, which are absorbed by the bottom cell, as shown in fig. 2A. Thus, the total current is determined by the battery cell having the smaller current output. Thus, the output current depends on photon recovery efficiency:

Where η _LC is the light coupling efficiency, which is mainly related to η _int and the collective shape of the optoelectronic device, namely:

Wherein, AndIs the probability that an internal photon will reabsorb inside the top cell layer 5 and couple to the bottom cell in the optoelectronic device, which is determined by the structure of the top cell layer 5 and the bottom cell layer 3. Further, it is possible to obtain:

In the embodiment of the disclosure, the η _int value obtained through the experiment is applied to the above formula, so that the output current I of the photoelectric device can be calculated, and a schematic diagram as shown in fig. 4C is obtained, and the calculation result is well matched with the experimental result and has a super-linear relationship with the excitation light power density. The difference between the experimental result and the calculation result shows that other non-radiative recombination mechanisms exist in the photoelectric device in the actual process. Consistent with the EQE results measured in fig. 1D, the light response at 475nm is several orders of magnitude lower than the light response at 810nm under low illumination conditions. When the illumination power is increased, the photocurrent at 475nm increases faster than the photocurrent at 810nm due to the enhanced photon recycling effect. Although two monochromatic light sources are used to study the operation of the optoelectronic device, other wavelengths of photons and carrier processes can be analyzed based on similar principles depending on the current matching/mismatch state. For this opto-electronic device, the EQE spectrum varies with illumination intensity variations at different wavelengths, which is predicted conceptually in fig. 4D, and ideally the EQE spectrum would appear stationary over a wide range as η _int approaches 100%, behaving like a single junction GaAs photodiode, but doubling the output voltage. In this case, most of the free carriers can undergo radiative recombination and form infrared photons that can be recovered by the bottom cell. Thus, the current can be matched between sub-cells of most wavelengths. It should be noted that photon recovery efficiency is reduced at ultra-high illumination power densities, since auger processes begin to dominate non-radiative recombination.

In another embodiment of the present disclosure, the top cell layer 5 is a GaAs cell layer, the bottom cell layer 3 is an InGaAs cell layer, as shown in fig. 5A, which is a schematic diagram of the response of the GaAs/InGaAs cell layer to different wavelengths, and as shown in fig. 5A, the absorption efficiency of GaAs/InGaAs of the bilayer structure of the top GaAs cell and the bottom InGaAs cell at different wavelengths is shown.

The conversion response of GaAs/InGaAs optoelectronic devices to different wavelengths is shown in fig. 5B with different photon recycling enhancement effects. As shown in fig. 5B, the GaAs/InGaAs spectral response efficiency of the bilayer structure is significantly enhanced by the photon recycling effect.

In another embodiment of the present disclosure, the top cell layer 5 is a GaAs cell layer, the bottom cell layer 3 is an InP cell layer, as shown in fig. 6A, which is a schematic diagram of the response of the GaAs/InP cell layer to different wavelengths, and as shown in fig. 6A, the absorption efficiency of GaAs/InP of the bilayer structure of the top GaAs cell layer and the bottom InP cell layer at different wavelengths is shown.

The conversion response of GaAs/InP photovoltaic devices to different wavelengths with different photon recycling enhancement is shown in fig. 6B. As shown in fig. 6B, the GaAs/InP spectral response efficiency of the bilayer structure is significantly enhanced by the photon recovery effect.

According to embodiments of the present disclosure, based on the optoelectronic performance of the optoelectronic device, strong illuminance and wavelength dependence associated with its corresponding photon recovery effect with different device layer thicknesses of its material were investigated. In addition, it has been demonstrated by research that the photon recovery effect also significantly affects photocurrent in multi-junction devices by changing photon coupling between subcells.

As shown in FIG. 7, the embodiment of the disclosure provides a preparation method of a photoelectric device based on photoelectric recovery effect enhancement, which comprises the steps of S1, sequentially growing a bottom cell layer, a high-doped tunnel junction layer and a top cell layer on a substrate, S2, forming a P-type electrode layer on one side of the substrate by adopting evaporated metal, and S3, forming an N-type electrode layer on one side of the top cell layer by adopting evaporated metal.

Wherein the photoelectric device is produced by using a metal organic chemical vapor deposition MOCVD method, the substrate is a GaAs substrate, the P-type electrode layer is formed by sequentially laminating and growing Cr and Au metals, a bottom cell layer having a layer thickness of 200nm and comprising a P-type InGaP-BSF layer, a P-type GaAs substrate, sequentially grown on the surface of the substrate, An N-type GaAs emitter and an N-type Al _0.3Ga_0.7 As window, wherein, the P-type InGaP-BSF layer is formed by Mg doping with doping concentration of 1 multiplied by 10 ¹⁸cm^-3, the layer thickness is 500nm, the P-type GaAs substrate is formed by Zn doping with doping concentration of 1 multiplied by 10 ¹⁷cm^-3, the layer thickness is 450nm, the N-type GaAs emitter is formed by Si doping with doping concentration of 2 multiplied by 10 ¹⁸cm^-3, the layer thickness is 100nm, the N-type Al _0.3Ga_0.7 As window is formed by Si doping with doping concentration of 2 multiplied by 10 ¹⁸cm^-3, and the layer thickness is 30nm; the high doped tunnel junction layer is arranged between a bottom cell layer and a top cell layer and used for providing a connection effect with low resistance and optical loss, and comprises an N-type GaAs layer and a P-type GaAs layer which are sequentially arranged on the surface of the bottom cell, wherein the N-type GaAs layer is an N-type GaAs layer with Se doping concentration of 9 multiplied by 10 ¹⁹cm^-3, the thickness of the N-type GaAs layer is 11nm, the P-type GaAs layer is a P-type GaAs layer with C doping concentration of 8 multiplied by 10 ¹⁹cm^-3, the thickness of the P-type GaAs layer is 11nm, the top cell layer is arranged on the high doped tunnel junction layer, wherein the energy band width of the top cell layer is larger than or equal to the energy band width of the bottom cell layer, and the top cell layer comprises a P-type Al _0.3Ga_0.7 As-BSF layer sequentially grown on the surface of the high doped tunnel junction layer, a p-type GaAs base electrode, An N-type GaAs emitter and an N-type InGaP window, the p-type Al _0.3Ga_0.7 As-BSF layer is formed by Mg doping with a doping concentration of 5×10 ¹⁸cm^-3, the layer thickness is 100nm, the p-type GaAs base is formed by Zn doping with a doping concentration of 1×10 ¹⁷cm^-3, the layer thickness is 1500nm, the N-type GaAs emitter is formed by a Si doping with a doping concentration of 2×10 ¹⁸cm^-3, the layer thickness is 100nm, the N-type InGaP window is formed by a Si doping with a doping concentration of 2×10 ¹⁸cm^-3, the layer thickness is 30nm, the N-type electrode layer is positioned at one end of the surface of the top battery layer, and the N-type electrode layer is formed by Ge the Ni and Au metals are sequentially formed by lamination growth, the thickness of the layers is 200nm, wherein the bottom battery layer and the top battery layer are used for absorbing excitation light photons and converting the excitation light photons into electrons, and the P-type electrode layer and the N-type electrode layer are used for forming good ohmic contact with an external circuit.

According to an embodiment of the disclosure, a sacrificial layer is grown between the substrate and the bottom cell, the sacrificial layer is Al _0.95Ga_0.05 As, the thickness of the sacrificial layer is 500nm, the Al0.95Ga0.05As sacrificial layer is removed through diluted hydrofluoric acid HF solution, and a separate film is formed, wherein the HF solution volume ratio is HF:water=1:10, and a small amount of ethanol is contained. Finally, the released photovoltaic device is picked up using a patterned Polydimethylsiloxane (PDMS) stamp and then transferred to a variety of carrier substrates with spin-on adhesive layers, such as glass, polyimide films, and silicon, etc. surfaces.

The disclosure also discloses application of the photoelectric device based on the photoelectric recovery effect enhancement in a high-performance photoelectric device.

Specifically, the photoelectric device based on the enhancement of the photoelectric recovery effect can realize the high-performance photon circulation effect of a solar battery, a photoelectric detector, a Light Emitting Diode (LED), a laser and the like, so that each photoelectric device has ultrahigh power conversion efficiency based on the improved photon recovery effect.

In the embodiments of the disclosure, the materials and layer thicknesses of the material layers are not limited to those shown in the foregoing, and may be adjusted according to the actual requirements.

While the disclosure has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive.

Those skilled in the art will appreciate that the features recited in the various embodiments of the disclosure and/or the claims can be combined in a wide variety of combinations and/or combinations even if such combinations or combinations are not explicitly recited in the disclosure. In particular, the features recited in the various embodiments of the present disclosure and/or the claims may be variously combined and/or combined without departing from the spirit and teachings of the present disclosure. All such combinations and/or combinations fall within the scope of the present disclosure.

While the present disclosure has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents. The scope of the disclosure should, therefore, not be limited to the above-described embodiments, but should be determined not only by the following claims, but also by the equivalents of the following claims.

Claims

1. An optoelectronic device based on enhanced photoelectric recycling effect, comprising:

A substrate;

a P-type electrode layer positioned at one end of the surface of the substrate;

the bottom battery layer is positioned at the other end of the surface of the substrate so as to be connected with the P-type electrode layer, and is used for absorbing excitation light photons and converting the excitation light photons into electrons so as to realize photoelectric-electro-optical conversion;

a highly doped tunnel junction layer on the bottom cell for providing a low resistance and optically low loss connection;

The top battery layer is positioned on the high-doped tunnel junction layer and is used for absorbing excitation light photons to convert the excitation light photons into electrons so as to realize photoelectric conversion, wherein the energy band width of the top battery layer is larger than or equal to that of the bottom battery layer;

An N-type electrode layer positioned at one end of the surface of the top battery layer;

Wherein the bottom cell layer is an InGaAs cell layer or an InP cell layer;

the top cell layer is a GaAs cell layer.

2. The photoelectric device based on the enhancement of the photoelectric recovery effect according to claim 1, wherein the internal quantum efficiency of the photoelectric device is

The following relationship is satisfied:

where R is a function related to excess carrier density, B is a constant of 1.5X10 ^-10 s^-1cm³, For the hole density in the thermal equilibrium state of the optoelectronic device,For the excess hole density of the photovoltaic device,Electron density for the thermal equilibrium state of the optoelectronic device,For the excess electron density of the optoelectronic device,Is the density of intrinsic carriers.

3. The photoelectric device based on the enhancement of the photoelectric recovery effect according to claim 1, wherein the P-type electrode layer and the N-type electrode layer are biased by direct current, and the current I in the photoelectric device and the internal quantum efficiency thereof

The following relationship is satisfied:

Wherein, A current that is the photon flux of the incident excitation light.

4. The photovoltaic device based on enhanced recycling of light effect according to claim 1, wherein the layer thickness of the top cell layer is less than the layer thickness of the bottom cell.

5. The photoelectric device based on the enhancement of the photoelectric recovery effect according to claim 1, wherein the N-type electrode layer is formed by sequentially stacking and growing Ge, ni and Au metals.

6. The photoelectric device based on the enhancement of the photoelectric recovery effect according to claim 1, wherein the P-type electrode layer is formed by sequentially stacking Cr and Au metals for growth.

7. A method for manufacturing a photoelectric device based on enhanced photoelectric recovery effect applied to the photoelectric device based on enhanced photoelectric recovery effect according to any one of claims 1 to 6, comprising:

S1, sequentially growing a bottom battery layer, a high-doped tunnel junction layer and a top battery layer on a substrate;

S2, forming a P-type electrode layer on one side of the substrate by adopting evaporated metal;

And S3, forming an N-type electrode layer on one side of the top battery layer by adopting evaporated metal.

8. Use of an optoelectronic device based on enhanced photoelectric recovery effect according to any one of claims 1 to 6 in a high performance optoelectronic device.