CN112271257B - A kind of preparation method of stretchable semiconductor device - Google Patents

Abstract

The invention relates to a preparation method of a stretchable semiconductor device, which comprises the following steps: forming a substrate sacrificial layer on a substrate; forming a substrate on the base plate sacrificial layer; forming a first electrode sacrificial layer on a substrate; forming a first electrode on the first electrode sacrificial layer; removing the first electrode sacrificial layer; forming a dielectric layer on the first electrode; forming a second electrode sacrificial layer on the dielectric layer; forming a second electrode and a third electrode on the second electrode sacrificial layer; forming a channel layer between the second electrodes; and removing the second electrode sacrificial layer. The invention further includes another method of making a stretchable semiconductor device.

Description

A kind of preparation method of stretchable semiconductor device

technical field

The present invention relates to a preparation method, in particular to a preparation method of a stretchable semiconductor device.

Background technique

Stretchable semiconductor devices can be roughly classified into two types: intrinsically stretchable and extrinsically stretchable. Extrinsic stretchable semiconductor devices can achieve certain stretchability by fabricating traditional hard materials into special structures or using special methods. However, these processing methods will be affected and limited in large-area patterning, work stability, and stretchability. The preparation materials of intrinsically stretchable semiconductor devices, including substrates, dielectric layers, electrodes, semiconductor layers, and interconnects are all stretchable structures. Intrinsically stretchable semiconductors have advantages in large-area integration and tensile stability.

Fabrication of intrinsically stretchable semiconductor devices requires the use of stretchable materials, but most of these materials are solution-based. Stretchable semiconductor devices are structurally stacked, and when the next layer of material is deposited based on solution methods , may cause damage to the prepared base material, causing problems including dissolution, mixing or wrinkling. Therefore, each layer structure is usually prepared separately, and then the multilayer structure is transferred to the same substrate through a multi-step transfer process, thereby completing the fabrication of intrinsically stretchable semiconductor devices. However, since such a process requires a complicated alignment operation during the transfer process, the size of the fabricated device is large, which affects the device integration density, and at the same time, the device yield is also low.

In recent years, inkjet printing has provided a solution to achieve non-destructive device integration, and significant progress has been made in fabricating stretchable semiconductors by choosing suitable orthogonal inks to avoid material miscibility. However, limited by current inkjet printing technology, stretchable semiconductor devices prepared by printing often exhibit relatively low graphic resolution, thus limiting the further reduction of device feature size. At the same time, there are still certain difficulties in achieving the stability of printing inks, especially in the preparation of inks for new materials. These factors limit the realization of high integration through the printing process.

Therefore, finding a way to fabricate intrinsically stretchable semiconductor devices with high stretchability, high electrical performance, small feature size, and mass production at the same time is crucial for the development of stretchable semiconductor devices.

SUMMARY OF THE INVENTION

In view of the technical problems existing in the prior art, the present invention provides a method for preparing a stretchable semiconductor device, which includes: forming a substrate sacrificial layer on a substrate; forming a substrate on the substrate sacrificial layer; forming a first substrate on the substrate an electrode sacrificial layer; forming a first electrode layer on the first electrode sacrificial layer and patterning it to form a first electrode; removing the first electrode sacrificial layer; forming a dielectric layer on the first electrode; on the dielectric layer forming a second electrode sacrificial layer; forming a second electrode layer on the second electrode sacrificial layer, and patterning it to form a second electrode and a third electrode; forming a channel layer between the second electrode and the third electrode, and patterning it to form a channel; and removing the second electrode sacrificial layer.

In particular, after forming the first electrode sacrificial layer and/or the second electrode sacrificial layer, the method further includes: pre-baking treatment.

Particularly, the substrate material includes silicon wafer or glass.

Particularly, the material of the substrate sacrificial layer includes dextran or PVA.

In particular, the substrate material includes PDMS, Ecoflex or PUU.

Particularly, the material of the first electrode sacrificial layer and/or the second electrode sacrificial layer includes IGZO or Al ₂ O ₃ .

Particularly, the first electrode, the second electrode material and/or the third electrode include metallic carbon nanotubes or conductive nanowires.

Particularly, the dielectric layer material includes PUU, PDMS or SEBS.

Particularly, the channel layer material includes semiconducting carbon nanotubes.

In particular, the formation process of the substrate sacrificial layer and/or the dielectric layer further includes a curing process, the curing temperature is 20°C to 100°C, and the curing time is 1 hour to 12 hours, wherein the curing temperature and the curing time are different. inversely proportional.

In particular, before forming the substrate sacrificial layer, the method further includes: performing hydrophilic treatment on the substrate.

Particularly, after removing the second electrode sacrificial layer, the method further includes: removing the substrate sacrificial layer.

The present invention further includes a method for fabricating a stretchable semiconductor device, comprising: forming a substrate sacrificial layer on a substrate; forming a substrate on the substrate sacrificial layer; forming a first electrode sacrificial layer on the substrate; forming a first electrode layer on the sacrificial layer and patterning it to form a second electrode and a third electrode; forming a channel layer between the second electrode and the third electrode, and patterning it to form a channel; removing the first electrode electrode sacrificial layer; forming a dielectric layer on the second electrode, the third electrode and the channel; forming a second electrode sacrificial layer on the dielectric layer; forming a second electrode layer on the second electrode sacrificial layer and patterning it forming a first electrode; removing the second electrode sacrificial layer.

In particular, after forming the first electrode sacrificial layer and/or the second electrode sacrificial layer, the method further includes: pre-baking treatment.

Particularly, the substrate material includes silicon wafer or glass.

Particularly, the material of the substrate sacrificial layer includes dextran or PVA.

In particular, the substrate material includes PDMS, Ecoflex or PUU.

Particularly, the material of the first electrode sacrificial layer and/or the second electrode sacrificial layer includes IGZO or Al ₂ O ₃ .

Particularly, the materials of the first electrode, the second electrode and/or the third electrode include metallic carbon nanotubes or conductive nanowires.

Particularly, the dielectric layer material includes PUU, PDMS or SEBS.

Particularly, the channel layer material includes semiconducting carbon nanotubes.

In particular, the formation process of the substrate sacrificial layer and/or the dielectric layer further includes a curing process, the curing temperature is 20°C to 100°C, and the curing time is 1 hour to 12 hours, wherein the curing temperature and the curing time are different. inversely proportional.

In particular, before forming the substrate sacrificial layer, the method further includes: performing hydrophilic treatment on the substrate.

Particularly, after removing the second electrode sacrificial layer, the method further includes: removing the substrate sacrificial layer.

Description of drawings

Below, the preferred embodiments of the present invention will be described in further detail in conjunction with the accompanying drawings, wherein:

1A to 1L are schematic diagrams illustrating the structure of a device prepared by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention;

2A-2L are perspective views of device structures prepared by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention;

3 is a schematic flowchart of a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention;

4A is a drawing state diagram of a stretchable semiconductor prepared by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention;

4B is an I _DS - V _GS relationship diagram of a stretchable semiconductor prepared by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention under different stretches;

FIG. 4C is a graph showing the relationship between stretchability, mobility and subthreshold swing of a stretchable semiconductor fabricated by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In the following detailed description, reference may be made to the accompanying drawings, which are considered a part of this application to illustrate specific embodiments of the application. In the figures, like reference numerals describe substantially similar components in the different figures. The specific embodiments of the present application are described in sufficient detail below to enable those of ordinary skill with relevant knowledge and technology in the art to implement the technical solutions of the present application. It should be understood that other embodiments may also be utilized or structural, logical or electrical changes may be made to the embodiments of the present application.

In order to fabricate intrinsically stretchable semiconductor devices with high stretchability, high electrical performance, small feature size, and mass production, traditional processes of photolithography and plasma etching have been developed in terms of process compatibility, equipment maturity, and low cost. Has many advantages. However, most stretchable organic elastomers are not resistant to plasma etching, and it is difficult to deposit other materials directly on them by solution methods. Therefore, in the process of fabricating stretchable semiconductor devices based on photolithography, the introduction of It is particularly important to select the protective layer of the material system. However, the introduction of an inorganic protective layer will cause the electrical properties of the transistor to be significantly degraded after stretching. Therefore, the development of stretchable semiconductor devices on lithographic platforms has been slow.

The present application provides a method for preparing an intrinsically stretchable semiconductor device, which avoids the previous problems while utilizing the advantages of photolithography and plasma etching, such as alignment effects, and achieves high stretchability, Fabrication of stretchable semiconductor devices with high electrical stability and small size.

Below, the preferred embodiments of the present invention will be described in further detail in conjunction with the accompanying drawings, wherein:

1A to 1L are schematic diagrams illustrating the structure of a device prepared by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention, and FIGS. 2A to 2L are the fabrication of a stretchable semiconductor device according to an embodiment of the present invention. The method is a perspective view of a device structure, and FIG. 3 is a schematic flowchart of a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention. 2A to 2L correspond to the structures in FIGS. 1A to 1L one-to-one, and FIG. 3 corresponds to the steps in FIGS. 1A to 1L one-to-one. The present application will be described in detail below with reference to the accompanying drawings. The method steps involved are only exemplary representations, and only one bottom-gate transistor is shown in the figure. As known to those skilled in the art, the disclosed method is also applicable to other types of semiconductor devices, such as diodes and the like.

In the methods involved in the present application, unless otherwise specified, the polymer curing process is not repeated in the steps. In some embodiments, the curing temperature is 20°C to 100°C, the curing time is 1 hour to 12 hours, and the curing time and curing temperature are inversely proportional. Without special instructions, the curing process is not reflected in the steps.

Step 1001 : hydrophilic treatment on the surface of the substrate. According to one embodiment, the substrate may include a silicon wafer, and the hydrophilic treatment may include oxygen plasma treatment.

In some embodiments, as shown in FIG. 1A and FIG. 2A , a silicon wafer is used as the substrate 101 in the preparation process, and the surface of the substrate 101 is first treated with oxygen plasma at a power of 100 W for 5 minutes. The hydrophilicity of the processed substrate 101 is improved. In some embodiments, the substrate 101 may be a silicon wafer, or may be replaced by other hard materials, such as glass. Of course, other methods can also be used to perform hydrophilic treatment on the substrate 101 .

Step 1002 : forming a substrate sacrificial layer on the substrate. According to one embodiment, the substrate sacrificial layer may include dextran.

In some embodiments, as shown in FIGS. 1B and 2B , dextran was dissolved in deionized water at a ratio of 1:10 and agitated at 40° C. for 1 hour to form a dextran solution. The dextran solution was spin-coated on the surface of the substrate 101 at 2000 rpm for 50 s to obtain the substrate sacrificial layer 102 with a thickness of 550 nm. Then bake on a heating plate at 120°C for 5 min. Of course, other methods can also be used to form the substrate sacrificial layer 102 . In some embodiments, the substrate sacrificial layer 102 can also be made of other materials, such as PVA, as long as the material is water-soluble and has no effect on other structures of the device.

Although the stretchable semiconductor device involved in the present application is an intrinsically stretchable device, a rigid structure (such as a substrate) is still required as a supporting structure for the semiconductor device during the fabrication process. After fabrication, the stretchable semiconductor device needs to be separated from the rigid support structure. The substrate sacrificial layer can exist as a transition layer between the two. It is filled between the substrate and the stretchable semiconductor device during the preparation process, and can be easily removed after the preparation to realize the separation of the substrate and the stretchable semiconductor device.

Step 1003 : forming a substrate on the sacrificial layer of the substrate. According to one embodiment, the substrate may comprise PDMS material.

In some embodiments, as shown in Figures 1C and 2C, the prepolymer and curing agent are mixed in a mass ratio of 10:1 to form the PDMS solution. The solution containing PDMS was spin-coated on the surface of the substrate sacrificial layer 102 at a speed of 800 rpm for 60 s. Then, the semiconductor device was processed for 15 min under a constant temperature of 70°C. After that, the PDMS solution was spin-coated again at 1500 rpm and 3000 rpm, respectively. A stretchable dielectric film with a thickness of about 1.25 μm is formed, which is the substrate 103 . Then, under the constant temperature condition of 70° C., the semiconductor device was placed for an additional 2 h. Of course, other methods can also be used to form the PDMS layer. In some embodiments, the substrate 103 can also be made of other elastic materials, such as Ecoflex, PUU, and the like.

Step 1004 : forming a first electrode sacrificial layer on the substrate. According to one embodiment, the first electrode sacrificial layer may include IGZO.

In some embodiments, as shown in FIG. 1D and FIG. 2D , in an argon atmosphere, the oxygen concentration is 6%, and the gas pressure is 0.43Pa, IGZO is magnetron sputtered with a power of 100w for 85s. A first electrode sacrificial layer 104 is formed on the substrate 103 with a thickness of 12 nm. In some embodiments, the first electrode sacrificial layer 104 may include other inorganic materials having acid etchability, such as Al ₂ O ₃ and the like. Of course, other methods can also be used to form the first electrode sacrificial layer 104 .

The first electrode sacrificial layer 104 can protect the substrate 103 from being damaged by oxygen plasma during the patterning process of the counter electrode. At the same time, the wettability of the substrate 103 is improved to increase the tube density of the carbon nanotubes spin-coated thereon.

In some embodiments, in order to release thermal stress, a device pre-baking process is further included after forming the first electrode sacrificial layer 104 .

Step 1005 : forming a first electrode layer on the first electrode sacrificial layer, and patterning it to form a first electrode. According to one embodiment, the material of the first electrode layer may include metallic carbon nanotubes.

In some embodiments, as shown in FIGS. 1E and 2E , an aqueous dispersion (0.9 wt %) of metallic carbon nanotubes (M-CNTs) was spin-coated onto the first electrode sacrificial layer 104 at 4000 rpm for 40 s. After the spin coating is completed, the semiconductor device is annealed at 120° C. for 10 minutes to form a first electrode layer. After that, it is patterned into the first electrode 105 by photolithography and oxygen plasma etching. The oxygen plasma etching parameters were 3 l·min ⁻¹ for oxygen, 5 sccm for nitrogen, 100 w for power, and 45 minutes for the duration. Of course, other methods can also be used to form the first electrode 105 . According to one embodiment, the first electrode layer 105 may be patterned using plasma etching to form the first electrode.

In some embodiments, the first electrode 105 is configured as a gate electrode of a transistor.

Step 1006: Remove the first electrode sacrificial layer.

In some embodiments, as shown in FIGS. 1F and 2F , the current semiconductor device is immersed in a hydrochloric acid solution (diluted 1:50 in deionized water) to remove the first electrode sacrificial layer 104 . The first electrode 105 is attached to the substrate 103 . The semiconductor device was then taken out and dried at 120° C. for 5 min. Of course, other methods can also be used to remove the first electrode sacrificial layer.

The first electrode sacrificial layer during the formation of the first electrode 105 protects the substrate 103 from being damaged by the oxygen plasma during the patterning process. At the same time, the wettability of the substrate 103 is improved to increase the tube density of the carbon nanotubes spin-coated thereon. During the etching process, due to the existence of voids between the carbon nanotubes, hydrochloric acid can etch the electrode sacrificial layer through these voids. The etching speed of the first electrode sacrificial layer in the longitudinal direction is greater than the etching speed in the lateral direction. After the first electrode sacrificial layer is etched away, the electrode can be dropped in a vertical direction at the original position and attached to the substrate without drifting. After the first electrode 105 is formed, the electrode sacrificial layer itself is no longer the required structure of the device. Removing the electrode sacrificial layer by hydrochloric acid can not only avoid affecting the electrical and mechanical properties of the stretchable semiconductor device in the tensile test, but also remove the The residual dispersant in the carbon nanotubes has no effect on other structures of the device.

Step 1007 : forming a dielectric layer on the first electrode. According to one embodiment, the dielectric layer may include a PUU.

In some embodiments, as shown in FIG. 1G and FIG. 2G , PPG-TDI and APDS were first mixed in tetrahydrofuran at a ratio of 100:10.7 to form a solution with a concentration of 170 mg·ml ⁻¹ , and then at 35° C. Stirred for 2 h, a PUU solution was formed. The PUU solution was spin-coated on the first electrode 105 at 5000 rpm for 50 s to form a 1 μm dielectric layer 106 . It was then annealed at 100°C for 5 hours to remove the THF solvent. Of course, other methods can also be used to form the dielectric layer 106 . In some embodiments, the dielectric layer 106 may include other corrosion-resistant organic elastic dielectric materials, such as PDMS, SEBS, and the like.

Step 1008 : forming a second electrode sacrificial layer on the dielectric layer.

In some embodiments, as shown in FIG. 1H , a second electrode sacrificial layer 107 is formed on the dielectric layer 106 with a thickness of 12 nm by sputtering IGZO (parameters refer to step 1004 ). Of course, other methods can also be used to form the second electrode sacrificial layer 107 .

In some embodiments, in order to release thermal stress, a device pre-baking process is further included after the second electrode sacrificial layer 107 is formed.

The second electrode sacrificial layer 107 can protect the dielectric layer 106 from being damaged by oxygen plasma during the patterning process. At the same time, the wettability of the dielectric layer 106 is improved to increase the tube density of the carbon nanotubes spin-coated thereon.

Step 1009 : forming a second electrode layer on the second electrode sacrificial layer, and patterning it to form a second electrode and a third electrode.

In some embodiments, as shown in FIG. 1I , the prepared M-CNTs aqueous dispersion (0.3 wt %) was spin-coated on the second electrode sacrificial layer 107 at 3000 rpm for 40 s. Then, under the condition of 100° C., annealing is performed for 10 min to form a second electrode layer. It is then patterned into a second electrode 108 and a third electrode 109 by photolithography and oxygen plasma etching. Among them, the oxygen plasma etching parameters were 3 l·min ⁻¹ for oxygen, 5 sccm for nitrogen, 100 W power, and 40 min for the duration. In some embodiments, the second electrode is configured as a source electrode and a drain electrode of the transistor. Of course, other methods can also be used to form the second electrode 108 and the third electrode 109 .

Step 1010: Form a channel layer between the second electrode and the third electrode, and pattern it to form a channel.

In some embodiments, as shown in Figure 1J, CNTs (1.0-1.4 nm in diameter, 1-2 μm in length) were dispersed in DCE (1,2 dichloroethane) containing dispersant at a concentration of 0.01 mg mL ^-1 in solution. The solution was first sonicated for 30 minutes, and then spin-coated on the second sacrificial layer 108 at 1500 rpm for 40 s. After that, annealing was performed at 100° C. for 15 min to form a channel layer. The channel layer is then patterned by photolithography and oxygen plasma etching to form a channel 110 located above the gate electrode 105 and between the second electrode 108 and the third electrode 109 . Among them, the oxygen plasma etching parameters were 3 l·min ⁻¹ for oxygen, 5 sccm for nitrogen, 100 W power, and 25 min for the duration. In some embodiments, the channel 110 has a width of 20 μm and a length of 5-100 μm. Of course, other methods can also be used to form the channel 110 .

Step 1011: Remove the second electrode sacrificial layer.

In some embodiments, as shown in FIG. 1K , the semiconductor device is immersed in a hydrochloric acid solution (with the same concentration as above) for 100 s to remove the second electrode sacrificial layer 107 . The upper structure of the second electrode sacrificial layer 107 is attached to the lower structure thereof. Then, the newly obtained semiconductor device was heated to 70 °C for 2 h to improve the adhesion. Of course, other methods can also be used to remove the second electrode sacrificial layer.

The second electrode sacrificial layer 107 protects the dielectric layer 106 from being damaged by oxygen plasma during patterning during the formation of the second electrode 108, the third electrode 109 and the channel layer 110. At the same time, the wettability of the substrate 103 is improved to increase the tube density of the carbon nanotubes spin-coated thereon. During the etching process, due to the existence of voids between the carbon nanotubes, hydrochloric acid can etch the electrode sacrificial layer through these voids. The etching speed of the second electrode sacrificial layer in the longitudinal direction is greater than the etching speed in the lateral direction. After the second electrode sacrificial layer is etched away, the electrode and the channel layer can be dropped in the vertical direction at the original position and attached to the substrate without drifting. After the second electrode 108, the third electrode 109 and the channel layer 110 are formed, the second electrode sacrificial layer 107 itself is no longer the required structure of the device. Removing the electrode sacrificial layer by hydrochloric acid can not only avoid the influence of the tensile test Stretching the electrical and mechanical properties of semiconductor devices can also remove residual dispersants in carbon nanotubes without affecting other structures of the device.

Step 1012: Remove the substrate sacrificial layer.

In some embodiments, as shown in FIG. 1L, a corner of the semiconductor device is selected, the substrate 103 is partially peeled off from the substrate 101, and then the entire semiconductor device is immersed in deionized water. Since the substrate sacrificial layer 102 is soluble in water, after a certain period of time, the substrate sacrificial layer 102 disappears, and the stretchable semiconductor device is separated from the substrate 101 . The stretchable semiconductor device was dried by nitrogen and baked at 70°C for 10 min to obtain the final stretchable semiconductor device. Of course, other methods can also be used to remove the substrate sacrificial layer.

Formed in the above method is a bottom gate stretchable semiconductor device. Of course, in some embodiments, a top-gate stretchable semiconductor device may also be formed using a similar method. The methods for processing the substrate, forming the substrate sacrificial layer and the stretchable substrate are the same as the above-mentioned methods. The first electrode sacrificial layer can be formed on the stretchable substrate, and then the second electrode and the The third electrode (eg, source and drain) and the conductive channel, and then the first electrode sacrificial layer is removed. Then a dielectric layer is formed on the second and third electrodes and the conductive channel, a second electrode sacrificial layer is formed on the dielectric layer, and a first electrode (such as a gate electrode) is formed on the second electrode sacrificial layer, and then removed The second electrode sacrificial layer, and finally the stretchable semiconductor device is peeled off from the substrate by removing the substrate sacrificial layer.

The semiconductor device prepared by the method of the present application has the characteristics of excellent stretchability and stable electrical properties after stretching. 4A is a drawing state diagram of a stretchable semiconductor prepared by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention. The prepared semiconductor device, after stretching as shown in the figure, even after multiple stretching, its stretchability and electrical properties are still stable.

4B is a graph showing the relationship between I _DS and V _GS of the stretchable semiconductor prepared by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention under different stretch degrees. Among them, the experimental results shown in the figure are the relationship diagram of I _DS - V _GS under the condition of V _DS =-1V. In the figure, the curve 401 is the relationship curve of I _DS - V _GS under the condition that the stretched degree of the fabricated semiconductor device is 0% (unstretched). Curve 402 is the relationship between I _DS and V _GS after the fabricated semiconductor device is subjected to tensile deformation with a tensile degree of 10%. Curve 403 is the relationship between I _DS and V _GS of the fabricated semiconductor device after being subjected to tensile deformation with a tensile degree of 20%. Curve 404 is the relationship between I _DS and V _GS of the fabricated semiconductor device after being subjected to tensile deformation with a tensile degree of 30%. Curve 405 is the relationship between I _DS and V _GS of the fabricated semiconductor device after being subjected to tensile deformation with a tensile degree of 40%. Curve 406 is the I _DS - V _GS relationship of the fabricated semiconductor device after being subjected to a tensile deformation of 50% elongation. It can be clearly seen from the curves in the figure that in the case of different stretching degrees, the variation between the curves is very small.

FIG. 4C is a graph showing the relationship between stretchability, mobility and subthreshold swing of a stretchable semiconductor fabricated by a method for fabricating a stretchable semiconductor device according to an embodiment of the present invention. The curve 410 is the relationship between the carrier mobility and the stretch degree, and the curve 411 is the relationship between the device subthreshold swing and the stretch degree. It can be clearly seen from the curves in the figure that the overall rate of change of the two curves is very small when the degree of stretch is different.

FIG. 4B and FIG. 4C clearly show that the electrical properties of the semiconductor device prepared by the method involved in the present application are very stable when the stretching degree is changed.

The method described in this application uses a network of carbon nanotubes (or conductive nanowires) as source/drain/gate/channel layers to achieve high-performance intrinsically stretchable semiconductors. It is creatively proposed that an electrode sacrificial layer is added during the preparation process to improve the wettability of the substrate and the dielectric layer, and at the same time protect the substrate and the dielectric layer from being damaged by oxygen plasma during the patterning process. Also, the electrode sacrificial layer can be removed at the end of device fabrication, improving the stability of the stretchable semiconductor device during the stretching process. Compared with the existing stretchable semiconductors, the stretchable semiconductor devices prepared in the present application are smaller in size, higher in driving current density, and higher in field-effect mobility. The stretchable semiconductor device prepared by the method described in this application still maintains its excellent electrical properties under 50% tensile strain after 2000 stretching cycles.

The above-mentioned embodiments are only for the purpose of illustrating the present invention, rather than limiting the present invention. Those of ordinary skill in the relevant technical field can also make various changes and modifications without departing from the scope of the present invention. Therefore, all Equivalent technical solutions should also belong to the scope of the disclosure of the present invention.

Claims (24)

1. A method of making a stretchable semiconductor device, comprising:

forming a substrate sacrificial layer on a substrate;

forming a substrate on the base plate sacrificial layer;

forming a first electrode sacrificial layer on a substrate;

forming a first electrode layer on the first electrode sacrificial layer and patterning the first electrode layer to form a first electrode;

removing the first electrode sacrificial layer to enable the first electrode to fall and be attached to the substrate;

forming a dielectric layer on the first electrode;

forming a second electrode sacrificial layer on the dielectric layer;

forming a second electrode layer on the second electrode sacrificial layer, and patterning the second electrode layer to form a second electrode and a third electrode;

forming a channel layer between the second electrode and the third electrode, and patterning the channel layer to form a channel; and

removing the second electrode sacrificial layer to enable the second electrode, the third electrode and the channel layer to fall and be attached to the dielectric layer;

wherein the substrate, the first electrode, the second electrode, the third electrode, the channel, and the dielectric layer have stretchability.

2. The method of claim 1, further comprising, after forming the first and/or second electrode sacrificial layers: and (5) pre-baking treatment.

3. The method of claim 1, the substrate material comprising silicon wafer or glass.

4. The method of claim 1, the substrate sacrificial layer material comprising dextran or PVA.

5. The method of claim 1, the substrate material comprising PDMS, Ecoflex, or PUU.

6. The method of claim 1, the first and/or second electrode sacrificial layer material comprising IGZO or Al ₂ O ₃ 。

7. The method of claim 1, the first electrode, second electrode material, and/or third electrode comprising metallic carbon nanotubes or conductive nanowires.

8. The method of claim 1, wherein the dielectric layer material comprises PUU, PDMS, or SEBS.

9. The method of claim 1, wherein the channel layer material comprises semiconducting carbon nanotubes.

10. The method of claim 1, wherein the substrate sacrificial layer and/or dielectric layer forming process further comprises a curing process, wherein the curing temperature is 20 ℃ to 100 ℃ and the curing time is 1 hour to 12 hours, and wherein the curing temperature is inversely proportional to the curing time.

11. The method of claim 1, further comprising, prior to forming the substrate sacrificial layer: and carrying out hydrophilic treatment on the substrate.

12. The method of claim 1, further comprising, after removing the second electrode sacrificial layer: and removing the substrate sacrificial layer.

13. A method of making a stretchable semiconductor device, comprising:

forming a substrate sacrificial layer on a substrate;

forming a substrate on the base plate sacrificial layer;

forming a first electrode sacrificial layer on a substrate;

forming a first electrode layer on the first electrode sacrificial layer and patterning the first electrode layer to form a second electrode and a third electrode;

forming a channel layer between the second electrode and the third electrode, and patterning the channel layer to form a channel;

removing the first electrode sacrificial layer to enable the second electrode, the third electrode and the channel to fall and be attached to the substrate;

forming a dielectric layer on the second electrode, the third electrode and the channel;

forming a second electrode sacrificial layer on the dielectric layer;

forming a second electrode layer on the second electrode sacrificial layer and patterning the second electrode layer to form a first electrode;

removing the second electrode sacrificial layer to enable the first electrode to fall and be attached to the dielectric layer;

wherein the substrate, the first electrode, the second electrode, the third electrode, the channel, and the dielectric layer have stretchability.

14. The method of claim 13, further comprising, after forming the first and/or second electrode sacrificial layers: and (5) pre-baking treatment.

15. The method of claim 13, the substrate material comprising silicon wafer or glass.

16. The method of claim 13, the substrate sacrificial layer material comprising dextran or PVA.

17. The method of claim 13, the substrate material comprising PDMS, Ecoflex, or PUU.

18. The method of claim 13, the first and/or second electrode sacrificial layer material comprising IGZO or Al ₂ O ₃ 。

19. The method of claim 13, the first, second and/or third electrode material comprising metallic carbon nanotubes or conductive nanowires.

20. The method of claim 13, wherein the dielectric layer material comprises PUU, PDMS, or SEBS.

21. The method of claim 13, wherein the channel layer material comprises semiconducting carbon nanotubes.

22. The method of claim 13, wherein the substrate sacrificial layer and/or dielectric layer forming process further comprises a curing process, wherein the curing temperature is 20 ℃ to 100 ℃ and the curing time is 1 hour to 12 hours, and wherein the curing temperature is inversely proportional to the curing time.

23. The method of claim 13, further comprising, prior to forming the substrate sacrificial layer: and carrying out hydrophilic treatment on the substrate.

24. The method of claim 13, further comprising, after removing the second electrode sacrificial layer: and removing the substrate sacrificial layer.

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