CN117784454A - A high-bandwidth SOI modulator based on doped ridge optical waveguide - Google Patents

Abstract

The invention discloses a high-bandwidth SOI modulator based on doped ridge optical waveguide. The ridge optical waveguide is a ridge waveguide made of doped silicon, and its structure includes a P++ doped region, a P+ doped region, a P-doped region, a P-doped region, an N-doped region, and an N- doped region. Doped area, N+ doped area, N++ doped area, of which P doped area and N doped area are located in the central area of the ridge waveguide, P++, P+, P‑, N++, N+, N‑ doped areas are located in the flat plate waveguide region. By driving with traveling wave electrodes, the present invention can realize high-efficiency and high-bandwidth electro-optical modulation.

Description

A high-bandwidth SOI modulator based on doped ridge optical waveguide

Technical field

The invention belongs to the technical fields of integrated photonic devices and integrated optoelectronic devices, and in particular relates to a high-bandwidth SOI modulator based on a doped ridge optical waveguide.

Background technique

In order to break through the physical bottleneck of microelectronics technology and achieve data communication with larger bandwidth, lower delay and lower power consumption, integrated photonic technology has become a popular research direction in academic and industrial circles, among which silicon photonics (SiP) ) has developed rapidly because it is compatible with CMOS technology. The electro-optical modulator is one of the core devices of silicon-based photonic integrated chips. Its function is to load electrical signals onto optical carriers to achieve low-latency and high-rate transmission of optically-carried microwave signals, or to transmit optically-carried microwave signals in the optical domain. Microwave signals are processed.

Since the silicon material itself does not have a strong electro-optical effect, silicon-based phase modulators are mostly based on the plasma dispersion effect (PDE), which uses changes in carrier concentration to achieve changes in the optical refractive index. PN junctions, PIN junctions or silicon-insulator-silicon capacitor structures (silicon–insulator–silicon capacitors, SISCAPs) are formed in silicon materials by doping. When an external voltage is applied, the PN junction enhances its drift motion under reverse bias to realize carrier depletion, the PIN junction realizes carrier injection under forward bias, and the SISCAP structure realizes carrier injection under forward bias. Accumulation, respectively, realizes that the carrier concentration in the optical waveguide changes with the change of external bias voltage, thereby achieving the purpose of electro-optical modulation.

At present, the geometric structure of doped silicon-based optical waveguides is mostly ridge-type structure. High-speed silicon-based phase modulators are mostly doped as PN junctions, and the doping structure is mostly two-level doping or three-level doping, that is, the doping concentration decreases step by step from the electrode contact area at the edge to the central waveguide area. The higher the doping concentration of the central waveguide, the greater the change in carrier concentration caused by the external voltage change, and the higher the electro-optical modulation efficiency. However, high doping also leads to a larger junction capacitance of the PN junction, thereby increasing the loss of electrical signals on the modulator electrode, thereby reducing the electro-optical bandwidth. Based on the current doping scheme of silicon waveguides, the efficiency and bandwidth of silicon-based modulators have become two mutually restrictive indicators.

Contents of the invention

The purpose of the present invention is to provide a high-bandwidth SOI modulator based on a doped ridge optical waveguide. On the original two-level or three-level doping structure with gradually changing concentrations, the planar waveguides on both sides of the central area of the ridge waveguide are closely connected. A low-concentration doping region with a first-level doping concentration of 10 ¹⁶ cm ^-3 is added to the area, which can greatly reduce the junction capacitance of the PN junction, thereby reducing the electrical loss of the modulator. It can be used without affecting the modulation efficiency. In this case, the modulation bandwidth is increased to solve the technical problem that the efficiency and bandwidth of the silicon-based modulator are mutually restricted due to the doping scheme of the existing silicon waveguide.

In order to solve the above technical problems, the specific technical solutions of the present invention are as follows:

The high-bandwidth SOI modulator based on the doped ridge optical waveguide of the present invention loads the modulation signal voltage on the doped ridge optical waveguide through the traveling wave electrode to change the carrier doping concentration in the waveguide. , thereby changing the refractive index of the waveguide material, realizing the phase modulation function of the propagating light mode, and extending the driving of two doped ridge waveguides to form a Mach-Zehnder structure, which can realize the intensity modulation function. If multiple ridge doped waveguides are expanded, , can realize the function of a high-order modulator; the modulator is composed of a doped ridge optical waveguide and a traveling wave electrode. The ridge optical waveguide is a doped silicon ridge waveguide prepared by the SOI process. The doped ridge optical waveguide is The waveguide is embedded in the SiO2 cladding, and its cross-sectional structure includes P++ doped areas, P+ doped areas, P- doped areas, P doped areas, N doped areas, N- doped areas, N+ doped areas arranged in sequence. P-doped and N++ doped regions, where the P-doped region and N-doped region are located in the central region of the ridge waveguide. The height of the central region of the ridge waveguide is H _rib , and the P++, P+, P-, N-, N+, and N++ regions are located in the slab waveguide region; the height of the slab waveguide region is H _slab , and the height of the central region of the ridge waveguide H _rib is higher than that of the slab waveguide. The height of the region is H _slab ; the propagating light mode is located in the central region of the ridge waveguide where the P-doped region and the N-doped region are located; the P- and N-doped regions are located in the slab waveguide region close to both sides of the ridge central region. The doping concentration is on the order of 10 ¹⁵ cm ^-3 ~ 10 ¹⁶ cm ^-3 . The existence of P- and N- low doping concentration regions significantly reduces the AC junction capacitance of the modulator without affecting the modulation efficiency. This reduces the electrical loss of the modulator and greatly increases the electro-optical bandwidth; the P+ and N+ doped regions are doping transition regions, the P+ doped region is located between the P- doped region and the P++ doped region, and the N+ doped region Located between the N- doped region and the N++ doped region, the doping concentrations of the P+ and N+ doped regions are higher than the P- and N- regions and lower than the P++ and N++ doped regions; the P++ region and N++ of the ridge waveguide The area is the area in contact with the traveling wave electrode; the traveling wave electrode is located above the doped ridge waveguide and is directly connected to the doped silicon in the P++ area and N++ area of the doped ridge waveguide through the metal through holes on the traveling wave electrode. , forming an ohmic contact, and at the same time, the upper surface of the traveling wave electrode is connected to an external probe or a metal lead for external modulation electrical signal input and connection to the terminal impedance.

Further, the doping concentration range of the P++ doped region of the ridge optical waveguide is 1×10 ¹⁹ cm ^-3 ~ 1×10 ²² cm ^-3 , and its width W _P++ ranges from 1 μm to 6 μm.

Further, the doping concentration range of the N++ doped region of the ridge optical waveguide is 1×10 ¹⁹ cm ^-3 ~ 1×10 ²² cm ^-3 , and its width W _P++ ranges from 1 μm to 6 μm.

Further, the doping concentration range of the P+ doped region of the ridge optical waveguide is 5×10 ¹⁶ cm ^-3 ~ 1×10 ¹⁹ cm ^-3 , and its width W _P+ ranges from 0 to 1 μm.

Further, the doping concentration range of the N+ doped region of the ridge optical waveguide is 5×10 ¹⁶ cm ^-3 ~ 1×10 ¹⁹ cm ^-3 , and its width W _P+ ranges from 0 to 1 μm.

Further, the doping concentration range of the P-doped region of the ridge optical waveguide is 1×10 ¹⁵ cm ^-3 ~ 5×10 ¹⁶ cm ^-3 , and its width W _{P -} ranges from 200 nm to 2 μm.

Further, the doping concentration range of the N-doped region of the ridge optical waveguide is 1×10 ¹⁵ cm ^-3 ~ 5×10 ¹⁶ cm ^-3 , and its width W _{P -} ranges from 200 nm to 2 μm.

Further, the doping concentration range of the P-doped region of the ridge optical waveguide is 1×10 ¹⁷ cm ^-3 to 2×10 ¹⁸ cm ^-3 , and its width W _P ranges from 150 nm to 350 nm.

Further, the doping concentration range of the N-doped region of the ridge optical waveguide is 1×10 ¹⁷ cm ^-3 to 2×10 ¹⁸ cm ^-3 , and its width W _N ranges from 150 nm to 350 nm.

Further, the traveling wave electrode of the modulator includes a coplanar waveguide (CPW, also called ground-signal-ground, GSG electrode), a coplanar stripline (CPS) , also known as ground-signal, ground-signal, GS electrode), as well as GSGSG and GSSGSSG electrodes extended based on GSG electrode and GS electrode, used for single doped ridge waveguide or multiple doped ridge waveguides to drive.

A high-bandwidth SOI modulator based on doped ridge optical waveguide of the present invention has the following advantages:

(1) Compared with the prior art, the present invention provides a high-bandwidth SOI modulator based on a doped ridge optical waveguide. By adding a low-doping region with a concentration of 10 ¹⁶ cm ^-3 or 10 ¹⁵ cm ^-3 in a planar waveguide region close to the central region of the ridge waveguide, the AC junction capacitance of the doped PN junction can be significantly reduced without affecting the modulation efficiency of the modulator, effectively reducing the electrical loss of the modulator, and significantly improving the modulation bandwidth when equipped with a suitable slow-wave traveling wave electrode.

(2) Compared with the prior art, the process complexity required by the present invention is not significantly improved, and the concentration of the doping region and the width of the doping region have a larger process tolerance.

Description of drawings

Figure 1 is a schematic three-dimensional structural diagram of a high-bandwidth SOI modulator based on a doped ridge optical waveguide provided by the present invention;

Figure 2 is a schematic cross-sectional view of a high-bandwidth SOI modulator based on a doped ridge optical waveguide provided by the present invention;

Figure 3 is a schematic diagram of the three-dimensional structure of the doped ridge optical waveguide of the high-bandwidth SOI modulator based on the doped ridge optical waveguide provided by the present invention;

Figure 4 is a schematic cross-sectional view of the doped ridge optical waveguide of the high-bandwidth SOI modulator based on the doped ridge optical waveguide provided by the present invention;

Figure 5 is a schematic diagram of the relationship between the effective refractive index of the propagating light mode and the applied reverse bias voltage of the high-bandwidth SOI modulator based on the doped ridge optical waveguide provided by the present invention;

Figure 6 is a schematic diagram of the modulation efficiency of the high-bandwidth SOI modulator based on doped ridge optical waveguide provided by the present invention;

FIG7 is a schematic diagram of microwave loss of a SOI phase modulator based on a doped ridge optical waveguide according to the present invention;

Figure 8 is a schematic diagram of the microwave effective refractive index of the SOI phase modulator based on the doped ridge optical waveguide of the present invention;

Figure 9 is a schematic diagram of the characteristic impedance of the SOI phase modulator based on the doped ridge optical waveguide of the present invention;

Figure 10 is a schematic diagram of the electro-optical response of the SOI phase modulator based on the doped ridge optical waveguide of the present invention at a length of 2 mm.

Detailed ways

In order to better understand the purpose, structure and function of the present invention, a high-bandwidth SOI modulator based on a doped ridge optical waveguide of the present invention will be described in further detail below in conjunction with the accompanying drawings.

This embodiment provides a high-bandwidth SOI modulator based on a doped ridge optical waveguide. As shown in Figure 1, the modulator is composed of a doped ridge optical waveguide and a traveling wave electrode. The ridge optical waveguide is a doped silicon ridge waveguide prepared using the SOI process. The doped ridge waveguide is embedded in the SiO2 cladding, and the waveguide is connected to the "T" type GSG electrode. As shown in Figure 2, the cross-sectional structure includes P++ doped areas, P+ doped areas, P- doped areas, P doped areas, N doped areas, N- doped areas, N+ doped and N++ doped areas arranged in sequence. Impurity region, where the P-doped region and N-doped region are located in the central area of the ridge waveguide, the height of the central area of the ridge waveguide is H _rib , and the P++, P+, P-, N-, N+, and N++ areas are located in the flat waveguide area; The height of the slab waveguide region is H _slab , and the height H _rib of the central region of the ridge waveguide is higher than the height H _slab of the slab waveguide region; the propagating light mode is located in the central region of the ridge waveguide where the P-doped region and the N-doped region are located; P- and The N-doped region is located in the flat waveguide region close to both sides of the ridge central region, and its doping concentration is on the order of 10 ¹⁵ cm ^-3 ~ 10 ¹⁶ cm ^-3 ; the P+ and N+ doped regions are doping transition regions. The P+ doped region is located between the P- doped region and the P++ doped region, the N+ doped region is located between the N- doped region and the N++ doped region, and the doping concentrations of the P+ and N+ doped regions are higher than those of the P- and N-region, lower than the P++ and N++ doped regions; the P++ region and N++ region of the ridge waveguide are the areas in contact with the traveling wave electrode; the traveling wave electrode is located above the doped ridge waveguide, passing through the traveling wave electrode The metal through hole is directly connected to the doped silicon in the P++ region and N++ region of the doped ridge waveguide to form an ohmic contact. At the same time, the upper surface of the traveling wave electrode is connected to an external probe or metal lead for external modulation of electrical signals. Input and connection to terminal impedance.

Those skilled in the art can understand that in other embodiments, one doped ridge waveguide coupled with electrodes can be used to realize the function of the phase modulator, or two doped ridge waveguides can be used to form a Mach-Zehnder modulator. Realize the intensity modulation function, and also expand 3, 4, 5... doped ridge waveguides to realize the function of high-order modulator.

The P+ region and N+ region of the ridge-type doped optical waveguide range from 0 to 1 μm, that is, the P+ and N+ doped regions do not need to exist. The P- and N-doped regions range from 200 nm to 2 μm. The process structure process tolerance and doping process tolerance allowed by the present invention are relatively large.

In order to verify that the present invention can realize this function, the following verification example is carried out for explanation.

The working principle of a high-bandwidth SOI modulator based on a doped ridge optical waveguide is as follows: an electrical signal is loaded on the electrode of the modulator, and the voltage signal on the electrode changes the refractive index of the doped ridge optical waveguide, thereby changing the propagating light mode. phase to achieve the electro-optical phase modulation function.

This verification uses the finite element-based diffusion equation and Poisson equation solver and the overlap integration method to calculate the modulation efficiency. The finite element-based Maxwell equation solver and related calculation formulas are used to calculate and analyze the electrical parameters and electro-optical response.

This embodiment is based on the phase modulator of the doped ridge optical waveguide of the present invention and uses slow-wave GSG traveling wave electrodes. As shown in Figure 1, the doped ridge optical waveguide is located in the middle of one group of GS electrodes. The specific parameters of the traveling wave electrode are shown in Figure 2. The signal electrode width W _s is 20 μm, the ground electrode width W _g is 100 μm, the period P _t of the "T" type channel is 15 μm, l _t is 12 μm, W _t and t is both 3 μm, G _t =32 μm, and S _t =6 μm.

The three-dimensional structural diagram of the doped ridge waveguide is shown in Figure 3. The structure is fabricated on an SOI platform, a Si substrate, and a SiO ₂ buried layer to prepare the doped ridge waveguide of the present invention. The ridge waveguide is located in the SiO ₂ package. layer.

The detailed cross-sectional view of the doped ridge waveguide is shown in Figure 4. In this embodiment, the height H _rib of the central region of the doped ridge optical waveguide is 220 nm, and the height H _slab of the slab region is 90 nm. P++ region width is 2.5μm, doping concentration 1×10 ²⁰ cm ^-3 ; P+ region width is 400nm, doping concentration 2×10 ¹⁸ cm ^-3 ; P region width is 280nm, doping concentration 1.5×10 ¹⁸ cm ^-3 ; N The area width is 220nm, the doping concentration is 1.5×10 ¹⁸ cm ^-3 , the N+ area width is 400nm, the doping concentration is 2×10 ¹⁸ cm ^-3 ; the N++ area width is 2.5μm, the doping concentration is 1×10 ²⁰ cm ^-3 .

The relationship between the refractive index of doped silicon and the carrier concentration is as shown in formula (1)

Δn＝-3.64×10 ^-10 λ ² ×ΔN _e -3.51×10 ^-6 λ ² ×(ΔN _h ) ^0.8 (1)

In formula (1), Δn is the change in the refractive index of doped silicon, ΔN _e and ΔN _h are the changes in electron and hole concentrations respectively, and λ is the wavelength of propagating light. Due to changes in the external reverse bias voltage, the carrier concentration of the doped waveguide changes, which in turn changes the effective refractive index of the waveguide propagation light mode. The change relationship of the effective refractive index neff is as follows: formula (2)

In formula (2), E(x,y) represents the electric field of the propagating light mode at a certain point in the waveguide cross section, E ^* (x, y) is the conjugate of E(x, y), Δn(x, y, V) is the amount of change in the refractive index of the material at a certain point on the waveguide cross-section with the applied voltage, and ∫∫ds represents the area integral.

According to equations (1) and (2), the relationship between the effective refractive index of the optical mode of the phase modulator based on the doped ridge optical waveguide and the applied reverse bias voltage in the embodiment can be simulated and calculated. As shown in Figure 5, when the When the reverse bias voltage increases from 0V to 6V, the effective refractive index of the propagating light mode changes from 2.56583 to 2.56619.

Figure 6 shows the modulation efficiency of a phase modulator based on a doped ridge optical waveguide under different bias voltages. The unit V _π L means that the π phase shift of the propagating beam is achieved through the L length at the V _π bias. The modulation efficiency is different under different bias voltages. For example, under 4V reverse bias, the modulation efficiency is 1.24V·cm.

Based on the RLGC model of microwave circuits, the electrical parameters of the doped ridge waveguide, namely the distributed junction resistance and junction capacitance, are substituted into the calculation to obtain the microwave loss and microwave wave velocity of the modulator. The calculation method is as shown in formula (3):

In formula (3), γ is the propagation constant of the microwave signal transmitted on the traveling wave electrode of the modulator, R _tl is the distributed resistance, L _tl is the distributed inductance, G _ul is the distributed interelectrode conductance of the unloaded electrode, G _tpn is the distributed conductance converted from the junction resistance of the doped waveguide, C _ul is the distributed capacitance of the unloaded electrode, C _tpn is the distributed capacitance converted from the junction capacitance of the doped waveguide, j is the imaginary unit , ω is the microwave angular frequency. The real part α of γ represents the microwave loss, and the imaginary part β of γ represents the microwave phase constant.

The microwave loss of the phase modulator based on the doped ridge waveguide calculated based on formula (3) is shown in FIG7 . In the frequency range of 1 to 100 GHz, the microwave loss under a reverse bias of 4 V is less than 3.5 dB/mm, and the microwave loss under a reverse bias of 6 V is less than 3 dB/mm.

Figure 8 shows the microwave effective refractive index of the phase modulator based on doped ridge optical waveguide, which is also calculated based on formula (3). It can be seen that the microwave refractive index gradually stabilizes at around 3.9 as the frequency increases in the range of 1 to 100 GHz. Very close to the group refractive index of 3.93 for the propagating light mode.

Figure 9 shows the characteristic impedance of the phase modulator based on doped ridge optical waveguide. The calculation method is as follows: formula (4)

It can be seen that in the range of 1 to 100 GHz, the characteristic impedance of the modulator is basically maintained at around 52Ω, which basically matches the interface standard of 50Ω.

The electro-optic response calculation method of silicon-based electro-optic modulator is as follows

In formula (5-9), V _avg (ω _m ) represents the average voltage on the entire traveling wave electrode when propagating a microwave signal with an angular frequency of ω _m , ω _m is the microwave angular frequency, and ρ ₁ and ρ ₂ are the source ends. and the reflection coefficient of the terminal, E _g represents the source voltage, Z _g represents the internal resistance of the signal source, Z _L is the terminal load, Z ₀ is the characteristic impedance of the modulator, γ is the propagation of the microwave signal transmitted on the traveling wave electrode of the modulator Constant, β _O is the equivalent light propagation constant, c is the speed of light in vacuum, n _o is the group refractive index of the propagating light mode, ω ₀ is the reference frequency, j is the imaginary unit, l represents the length of the modulator, and l is used in the calculation =2mm, the standard value of Z _g =Z _L =50Ω is the same as the standard interface impedance of most commercial instruments, and other parameters have been obtained in previous calculations.

Figure 10 shows the electro-optical response of a phase modulator based on a doped ridge optical waveguide at a length of 2mm. Under a 4V bias voltage, its 3dB electro-optical bandwidth can reach 100GHz. There is a small drop in the low frequency band. Under a 6V bias voltage, the electro-optical response The response is higher than -3dB in the 100GHz range, that is, the 3dB electro-optical band can reach over 100GHz.

It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims (10)

1. A high-bandwidth silicon-on-insulation substrate SOI modulator based on a doped ridge optical waveguide, characterized in that the modulator is composed of a doped ridge optical waveguide and a traveling wave electrode; the ridge optical waveguide It is a doped silicon ridge waveguide prepared using the SOI process. The doped ridge waveguide is embedded in the SiO ₂ cladding. Its cross-sectional structure includes P++ doped regions, P+ doped regions, and P- doped regions arranged in sequence. , P doping region, N doping region, N- doping region, N+ doping and N++ doping region, where the P doping region and N doping region are located in the central area of the ridge waveguide, and the height of the central area of the ridge waveguide is H _rib , P++, P+, P-, N-, N+, and N++ regions are located in the slab waveguide region; the height of the slab waveguide region is H _slab , and the height H _rib of the central region of the ridge waveguide is higher than the height H _slab of the slab waveguide region; The propagating light mode is located in the central area of the ridge waveguide where the P-doped area and the N-doped area are located; the P- and N-doped areas are located in the flat waveguide area close to both sides of the ridge central area, and their doping concentration is 10 ¹⁵ cm ^-3 ~ 10 ¹⁶ cm ^-3 order of magnitude; P+ and N+ doped areas are doping transition areas, P+ doped area is located between P- doped area and P++ doped area, N+ doped area is located at N- doped area Between the P+ and N++ doped regions, the doping concentration of the P+ and N+ doped regions is higher than that of the P- and N- regions, but lower than the P++ and N++ doped regions; the P++ and N++ regions of the ridge waveguide are related to the traveling wave The area where the electrodes are in contact; the traveling wave electrode is located above the doped ridge waveguide, and is directly connected to the doped silicon in the P++ region and N++ region of the doped ridge waveguide through the metal through holes on the traveling wave electrode, forming an ohmic contact. At the same time, the upper surface of the traveling wave electrode is connected to an external probe or a metal lead for external modulation electrical signal input and connection to the terminal impedance. 2. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration of the P++ doped region ranges from 1×10 ¹⁹ cm ^-3 to 1×10 ²² cm ^-3 , and its width W _P++ ranges from 1 μm to 6 μm. 3. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration range of the N++ doped region is 1×10 ¹⁹ cm ^-3 ~ 1×10 ²² cm ^-3 , its width W _N++ ranges from 1μm to 6μm. 4. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration of the P+ doped region ranges from 5×10 ¹⁶ cm ^-3 to 1×10 ¹⁹ cm ^-3 , and its width W _P+ ranges from 0 to 1 μm. 5. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration range of the N+ doped region is 5×10 ¹⁶ cm ^-3 ~ 1×10 ¹⁹ cm ^-3 , its width W _N+ ranges from 0 to 1 μm. 6. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration of the P-doped region ranges from 1×10 ¹⁵ cm ^-3 to 5×10 ¹⁶ cm ^-3 , and its width W _P- ranges from 200 nm to 2 μm. 7. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration range of the N-doped region is 1×10 ¹⁵ cm ^-3 ~ 5×10 ¹⁶ cm ^-3 , and its width W _N- ranges from 200nm to 2μm. 8. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration range of the P-doped region is 1×10 ¹⁷ cm ^-3 ~ 2×10 ¹⁸ cm ^-3 , its width W _P ranges from 150nm to 350nm. 9. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the doping concentration range of the P-doped region is 1×10 ¹⁷ cm ^-3 ~ 2×10 ¹⁸ cm ^-3 , its width W _N ranges from 150nm to 350nm. 10. The high-bandwidth SOI modulator based on doped ridge optical waveguide according to claim 1, characterized in that the type of the traveling wave electrode includes a coplanar waveguide GSG electrode, a coplanar stripline GS electrode, and GSGSG and GSSGSSG electrodes are expanded on the basis of GSG electrode and GS electrode.