Longitudinal light-operated unit and semiconductor voltage-withstanding unit composite device and manufacturing method thereof

Abstract

The invention provides a longitudinal light-operated unit and semiconductor voltage-withstanding unit composite device and a manufacturing method thereof. A voltage-withstanding unit in the composite device is formed by jointly constructing an n-epitaxial layer, an n + epitaxial layer and a substrate layer; the electric control unit is formed by performing Si ion implantation on the n + epitaxial layer to form an n + + epitaxial layer, and the n + + epitaxial layer and the ohmic metal form a source electrode; gate dielectric / P + regions, gate metal and interlayer dielectric are sequentially arranged on two sides of the n + + epitaxial layer and the n + epitaxial layer respectively; the light-operated unit is formed in the mode that a groove structure is constructed on the n + epitaxial layer in the direction from the surface to the substrate layer, a P-type thin film layer is formed, the P-type thin film layer and the n + epitaxial layer form a PN junction to form a local depletion region, and a light-operated electrode is arranged on the inner wall side of the P-type thin film layer. A traditional silicon-based material is replaced with a wide bandgap semiconductor voltage-resistant material, structural innovation is carried out, the physical limit of the light-operated power device is fundamentally improved, and the corresponding light-operated power device can stably work under the higher temperature, the higher voltage and the more severe environment.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor devices, and in particular to a composite device of a longitudinal light control unit and a semiconductor withstand voltage unit and a manufacturing method thereof. Background Art

[0002] In today's power electronics applications with higher power density and lower power consumption requirements, Ga 2 O 3 The material has a greater research significance and a broader market application prospect. In contrast to the ease of n-type doping, there is currently no 2 O 3 The successful realization of p-type doping in Ga 2 O 3 Compared with materials that can be bipolar doped, their application in bipolar power devices is limited.

[0003] There are three factors that make p-type Ga conductive holes possible. 2 O 3 Almost impossible: First, it is difficult to find acceptor impurities with small activation energy; second, according to theoretical calculations, Ga 2 O 3 The valence band maximum dispersion is small, and the effective mass is very large, resulting in the free holes being almost localized to small μ; finally, in theory, it has been specifically designed for Ga 2 O 3 It is predicted that due to the local lattice distortion, the local self-trapping energy of free holes in the bulk is very large, which leads to the formation of small poles, which undoubtedly prohibits the conduction of effective holes.

[0004] In the existing technology, Ga 2 O 3 Taking materials as an example, there is no example of integrating the control unit and voltage-resistant unit of wide bandgap semiconductor materials with the light control unit on the same wafer substrate. The existing example is a silicon-based light control device, which has two technical problems: First, silicon material is the voltage-resistant unit of the entire device. Currently developed silicon-based high-voltage devices such as IGBT (insulated gate bipolar transistor), VDMOS (vertical double diffused metal oxide semiconductor) and GTO (thyristor) have almost reached the physical limit of silicon-based materials, and it is very difficult to further improve their voltage resistance. Secondly, the light control units of silicon-based light control devices all work near the surface of the electrode metal material. Since the silicon material itself is not transparent, when the light control unit starts to work, the depth of light entering from the surface of the silicon-based device is very thin and cannot reach the position of the voltage-resistant layer of the silicon-based device. At this time, the electron-hole pairs generated by the light are instantly recombined by the existing majority carriers in the neutral zone close to the surface, and no large current will be generated to turn on the device, so the purpose of light control cannot be achieved.

[0005] Based on this, the present invention provides a novel composite device of a longitudinal light control unit and a semiconductor voltage-resistant unit and a manufacturing method thereof. Summary of the invention

[0006] Based on the above description, the present invention provides a composite device of a longitudinal light control unit and a semiconductor voltage-resistant unit and a device structure to solve the problem in the prior art that silicon-based high-voltage devices have almost reached the physical limit of silicon-based materials, the depth of light entering from the surface of the silicon-based device is very thin and cannot reach the position of the voltage-resistant layer of the silicon-based device, and the purpose of light control cannot be achieved.

[0007] The technical solution of the present invention to solve the above technical problems is as follows: In a first aspect, the present invention provides a composite device of a longitudinal light control unit and a semiconductor voltage-resistant unit, comprising: a substrate layer, an n-epitaxial layer, an n+epitaxial layer, an n++epitaxial layer, a voltage-resistant unit, an electric control unit and a light control unit; The n- epitaxial layer and the n+ epitaxial layer are sequentially stacked on the substrate layer from bottom to top; The voltage-resistant unit is formed by constructing the n-epitaxial layer and the n+epitaxial layer together with the substrate layer; the electric control unit and the light control unit are respectively arranged on the voltage-resistant unit; The electric control unit is formed by performing Si ion implantation on the n+ epitaxial layer to form the n++ epitaxial layer, and the n++ epitaxial layer and the ohmic metal form a source electrode; the gate dielectric / P+ region, the gate metal and the interlayer dielectric are respectively provided on both sides of the n++ epitaxial layer and the n+ epitaxial layer; The light control unit is formed by constructing a groove structure from the surface of the n+ epitaxial layer toward the substrate layer, forming a P-type thin film layer by a sputtering stripping process, the P-type thin film layer and the n+ epitaxial layer form a PN junction to form a local depletion region, and a light control electrode is provided on the inner wall side of the P-type thin film layer.

[0008] Based on the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, the material of the substrate layer is an N-type high-resistance or high-purity semi-insulating semiconductor material, or a P-type or quasi-P-type material.

[0010] Furthermore, the composite device further includes a drain electrode; The drain electrode is arranged at the bottom of the substrate layer.

[0011] Furthermore, the P-type thin film layer is a transparent material.

[0012] Furthermore, a transparent metal layer is provided on the inner wall side of the P-type thin film layer.

[0013] Furthermore, the groove structure is a multi-level groove, a regular groove or an irregular groove.

[0014] Furthermore, the electric control unit is provided with one of a Fin structure, a JFET structure, a GAA structure, a MOS structure, a BJT structure, a PN structure, a PIN structure, a heterogeneous PN structure, an IGBT structure, a GTO structure and an SJ structure.

[0015] Furthermore, the n-epitaxial layer is Ga 2 O 3 , AlN, BN, SiC, GaN, diamond wide bandgap semiconductor materials or any combination thereof.

[0016] In a second aspect, the present invention further provides a method for manufacturing a composite device of a longitudinal light control unit and a semiconductor withstand voltage unit as described in the first aspect, characterized in that the method comprises the following steps: S1: constructing a current channel layer on the substrate layer and the surface of the n- epitaxial wafer, and sequentially forming an n+ epitaxial layer and an n++ epitaxial layer by ion implantation; S2: etching the n+ epitaxial layer and the n++ epitaxial layer; S3: growing a gate dielectric layer and a gate metal layer in sequence at the edge of the etching; S4: Use photoresist planarization process to expose the top gate metal; S5: etching the gate metal and the gate dielectric in sequence on the structure after the photoresist is planarized, and performing a resist stripping process after etching; S6: growing an interlayer dielectric, and then etching the interlayer dielectric to open holes; S7: selectively depositing source metal locally by evaporation and stripping, and then annealing to form ohmic contact, and the electronic control unit is completed; S8: protecting the electric control unit by applying glue, exposing and etching only the light control unit; etching the n+ epitaxial layer and the n++ epitaxial layer, and obtaining a groove structure by using a sidewall process; S9: growing a layer of transparent thin P-type material on the surface of the groove structure by a sputtering process to form a P-type thin film layer; S10: vapor-depositing a transparent metal on the P-type thin film layer to form a light-controlled electrode; annealing the transparent metal and the transparent P-type thin film layer to form an ohmic contact; flipping the device, vapor-depositing metal on the substrate layer, and annealing to form an ohmic contact to manufacture a drain electrode.

[0017] Compared with the prior art, the technical solution of this application has the following beneficial technical effects: Compared with the prior art, the composite device of the longitudinal light control unit and the semiconductor withstand voltage unit, the device structure and the manufacturing method thereof provided by the present invention have the following beneficial effects: The composite device of the longitudinal light control unit and the semiconductor voltage-withstand unit includes an N-type doped 4H-SiC substrate, an N-type doped epitaxial layer above the 4H-SiC substrate, an N-type doped 3C-SiC epitaxial layer above the N-type epitaxial layer, an epitaxial interface layer naturally generated between the N-type doped epitaxial layer and the 3C-SiC, an N-type doped carrier tunneling region penetrating part of the epitaxial interface layer, and a P-type doped buried layer below the N-type doped carrier tunneling region.

[0018] (1) A new type of gallium oxide light-controlled high-voltage and high-current power device was proposed for the first time by directly injecting photons into the body region of the wide-bandgap semiconductor material's voltage-resistant layer. This solution solves the problem of commercializing gallium oxide power devices in the absence of p-type doping in gallium oxide materials. That is, only n-type gallium oxide materials are used to realize ultra-high voltage and high current power devices.

[0019] (2) The structural design of combining the electric control unit with the optical control unit that penetrates into the epitaxial region of the trench composite structure can allow the photogenerated carriers to penetrate into the high-voltage-resistant body region inside the device structure, solving the problem that electron-hole pairs are formed on the surface of the material and then quickly recombine with multiple carriers in the neutral region, resulting in low on-current and insensitive optical control. At the same time, the ultra-high voltage switching process can be controlled by a low-voltage electric control unit. When the light control unit that penetrates deep into the epitaxial body area adopts a multi-level groove structure, the multi-level groove auxiliary light injection area structure can penetrate deep into the epitaxial voltage-resistant layer, and even penetrate the epitaxial layer into the voltage-resistant high-resistance substrate layer, thereby achieving a deeper photon injection conductivity modulation area with a high light injection total surface area ratio, which is beneficial to further reduce the on-resistance when the device is turned on by light.

[0020] (3) Replace traditional silicon-based materials with wide-bandgap semiconductor voltage-resistant materials such as gallium oxide, and innovate structural design to fundamentally improve the physical limits of light-controlled power devices and give full play to the material properties. The light-controlled power devices manufactured can work stably at higher temperatures, higher voltages, and in more severe environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1Schematic diagram of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 1 of the present invention; Figure 2 Equivalent model diagram of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 1 of the present invention; Figure 3 Principle schematic diagram of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 1 of the present invention; Figure 4 Schematic diagram of the manufacturing process of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 2 of the present invention; Figure 5 Schematic diagram of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 3 of the present invention; Figure 6 Schematic diagram of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 4 of the present invention; Figure 7 and Figure 8 Schematic diagram of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 5 of the present invention; Fig. 9 and Fig.10 Schematic diagram of the composite device of the longitudinal light control unit and the semiconductor voltage withstand unit provided in Embodiment 6 of the present invention; In the drawings, the list of components represented by each reference numeral is as follows: 1. Substrate layer; 2. n-epitaxial layer; 3. n+-epitaxial layer; 4. n++-epitaxial layer; 5. Voltage withstand unit; 6. Electric control unit; 7. Light control unit; 8. Gate dielectric; 9. P+ region; 10. Gate metal; 11. Interlayer dielectric; 12. Source electrode; 13. P-type thin film layer; 14. Light control electrode; 15. Drain electrode. Detailed implementation manners

[0022] For ease of understanding of the present application, the present application will be described more comprehensively below with reference to the relevant drawings. Embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present application is more thorough and comprehensive.

[0023] The following further describes in detail the implementation manners of the present invention with reference to the drawings and embodiments. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0024] Embodiment 1 As Figure 1As shown, this embodiment provides a composite device of a longitudinal light control unit and a semiconductor voltage-resistant unit, including: a substrate layer 1, an n- epitaxial layer 2, an n+ epitaxial layer 3, an n++ epitaxial layer 4, a voltage-resistant unit 5, an electric control unit 6 and a light control unit 7.

[0025] The n- epitaxial layer 2 and the n+ epitaxial layer 3 are sequentially stacked on the substrate layer 1 from bottom to top.

[0026] The material of the substrate layer 1 is an N-type high-resistance or high-purity semi-insulating semiconductor material, or a P-type or quasi-P-type material.

[0027] The n-epitaxial layer 2 is Ga 2 O 3 , AlN, BN, SiC, GaN, diamond wide bandgap semiconductor materials or any combination thereof. In a specific example, the material of the substrate layer 1 is gallium oxide.

[0028] The voltage-resistant unit 5 is formed by constructing the n- epitaxial layer 2 and the n+ epitaxial layer 3 together with the substrate layer 1; the electric control unit 6 and the light control unit 7 are respectively arranged on the voltage-resistant unit 5. The electric field diagram of the voltage-resistant unit 5 is shown in FIG. Figure 1 as shown on the left.

[0029] Among them, the electric control unit 6 is formed by performing Si ion implantation on the n+ epitaxial layer 3 to form an n++ epitaxial layer 4, and the n++ epitaxial layer 4 and the ohmic metal form a source electrode 12; the gate dielectric 8, the gate metal 10 and the interlayer dielectric 11 are respectively provided on both sides of the n++ epitaxial layer 4 and the n+ epitaxial layer 3.

[0030] The light control unit 7 is formed by constructing a groove structure in the n+ epitaxial layer 3 from the surface to the substrate layer 1, and forming a P-type thin film layer 13 through a sputtering stripping process. The P-type thin film layer 13 and the n+ epitaxial layer 3 form a PN junction to form a local depletion region, and a light control electrode 14 is provided on the inner wall side of the P-type thin film layer 13.

[0031] The P-type thin film layer 13 is made of transparent material.

[0032] like Figure 1 As shown, the light control electrode 14 on the inner wall side of the P-type thin film layer 13 is a transparent metal layer.

[0033] like Figure 2As shown, when light passes through the transparent electrode and the transparent P-type material and irradiates the depletion region in the n-epitaxial layer 2, the photons generate electron-hole pairs. Under high voltage and high field conditions, the newly generated electron-hole pairs will not recombine in the depletion region, but will be pulled to the two poles by the high field to form current, and continue to generate more new electron-hole pairs, so that the epitaxial layer with large on-resistance, due to the generation of a large number of electron-hole pairs, is replaced by light injection instead of traditional electrical injection, and finally the on-resistance is reduced, forming a large on-current. In this way, high-power pulse current can be controlled by controlling only the light intensity. When no light is applied, the device can withstand ultra-high working voltage through the thick n-epitaxial layer 2, realizing gallium oxide light-controlled high-voltage and high-current power devices.

[0034] Therefore, the setting of transparent materials and transparent metals can effectively ensure that light can be incident from this area to the depletion region in the voltage-resistant layer to form a large number of electron-hole pairs. Under the bias of an external high voltage, the electron-hole pairs move toward the source and the gate respectively, forming high-power current pulses, which play the role of light-controlled high voltage and large current.

[0035] Further, such as Figure 1 As shown, the composite device further includes a drain electrode 15 ; the drain electrode 15 is disposed at the bottom of the substrate layer 1 .

[0036] The groove structure is a multi-level groove, a regular groove or an irregular groove.

[0037] In this embodiment, the groove structure is a multi-level groove, and its structure can be but not limited to a two-level groove structure (n≥2). In a specific example, Figure 1 As shown, the multi-level grooves can be two-level grooves, which are defined as first-level grooves and second-level grooves in sequence from the surface to the substrate.

[0038] The electronic control unit 6 is provided with one of a Fin structure, a JFET structure, a GAA structure, a MOS structure, a BJT structure, a PN structure, a PIN structure, a heterogeneous PN structure, an IGBT structure, a GTO structure and a SJ structure. Figure 1 As shown, the electronic control unit 6 is preferably a Fin structure.

[0039] The use of gallium oxide materials to design the electric control unit 6 and the voltage-resistant unit 5, and integrating them with the light control unit 7 through technical means such as structural optimization, can perfectly solve the difficulties of voltage resistance and surface recombination encountered by the above-mentioned silicon-based light control devices, thereby further promoting the marketization of gallium oxide power device applications and providing potential possibilities.

[0040] Example 2 In order to facilitate the understanding of the composite device of the longitudinal light control unit and the semiconductor withstand voltage unit provided in Example 1, Figure 4 As shown, this embodiment provides a preparation method thereof: Step S1: constructing a current channel layer on the substrate layer and the surface of the n- epitaxial wafer, and sequentially forming an n+ epitaxial layer and an n++ epitaxial layer by ion implantation.

[0041] Specifically, the substrate layer and the n-type low-doped gallium oxide semiconductor epitaxial wafer (n--Ga 2 O 3 ) The surface current channel layer can be constructed by ion implantation. The injected ion source can be but not limited to Si or Sn elements. After ion implantation, annealing activation treatment is required to form n+ layer and n++ layer in sequence.

[0042] Step S2: etching the n+ epitaxial layer and the n++ epitaxial layer.

[0043] Specifically, BCl 3 The mixed gas of Ar and GaO is used to etch the n++ and n+ layers of the GaO epitaxial structure to form a Fin structure. The width of the Fin structure meets certain conditions and tries to meet W Fin <400nm.

[0044] Step S3: sequentially grow a gate dielectric layer (such as Al 2 O 3 ) and gate metal (such as Ni / Au).

[0045] Step S4: using a photoresist planarization process to expose the top gate metal.

[0046] Step S5: etching the gate metal and the gate dielectric in sequence on the structure after the photoresist is planarized, and performing a resist stripping process after etching.

[0047] Step S6: growing an interlayer dielectric (such as SiO 2 ), and then the interlayer dielectric is etched to open holes to facilitate the subsequent deposition of growth source metals (such as Ti / Au).

[0048] Step S7: selectively depositing source metal locally by evaporation and stripping, and then annealing to form ohmic contact, and the electronic control unit is completed.

[0049] Step S8: Protect the electronic control unit by applying glue, and only expose and etch the right light control unit; use BCl 3 The n+ epitaxial layer and the n++ epitaxial layer are etched with a mixed gas of Ar and, at the same time, a sidewall process is used to obtain a trench structure. Here, a two-level trench is taken as an example, that is, it is obtained by simultaneously using the sidewall process.

[0050] Step S9: A transparent thin P-type material, such as an AZO thin film material (transparent conductive thin film), is grown on the surface of the trench structure by a sputtering process, and the concentration of the transparent thin film P-type material is controllable to form a P-type thin film layer.

[0051] Step S10: A transparent metal is evaporated on the P-type thin film layer, and the transparent P-type thin film layer forms a light control electrode; an ohmic contact is formed after annealing the transparent metal and the transparent P-type thin film layer; the device is flipped, and a metal (which can be Ti / Au) is evaporated on the substrate layer, and an ohmic contact is also formed after annealing to manufacture a drain electrode, and finally a light control high-voltage large-current power device is formed.

[0052] After the above specific steps form a light control high-voltage large-current power device, its schematic diagram is as shown in Figure 3 As shown here, further introduction is made. The gate G voltage is normally applied with a positive voltage to control the conduction of the entire transistor. Electrons reach the drain D from the source S through a high-voltage electric field. However, due to the very large thickness of the n--Ga 2 O 3 epitaxial layer, the on-resistance of the device is extremely large. Even under the condition of applying a high voltage at the D end, the entire current of the device is still small, which is not conducive to cost and safety control.

[0053] Through the multi-level trench structure in the upper right, the P-type thin film material and the n--Ga 2 O 3 epitaxial layer form a depletion region, and the concentration of the P-type material is controlled to be more than 10 times that of the n--Ga 2 O 3 epitaxial layer. In this way, the width of the depletion region extends greatly in the n-type epitaxial layer. When light irradiates the depletion region in the n--Ga 2 O 3 epitaxial layer through the transparent electrode and the transparent P-type material, photons generate electron-hole pairs. Under the conditions of high voltage and high electric field, these electron-hole pairs will not recombine in the depletion region, but are respectively pulled to both poles by the high electric field to form a current, and continue to generate more new electron-hole pairs, making the epitaxial layer with a very large on-resistance, due to the generation of a large number of electron-hole pairs, the light injection replaces the traditional electric injection, and finally the on-resistance is reduced to form a large on-current. In this way, only by controlling the light intensity can a high-power pulsed current be controlled to be formed. When no light is applied, the device withstands an ultra-high working voltage through the thick n--Ga 2 O 3 epitaxial layer, and a gallium oxide light control high-voltage large-current power device is realized.

[0054] Example 3 Based on Example 1 and Example 2, the difference is that: The Fin structure may also be one or a combination of several of a JFET structure, a GAA structure, a MOS structure, a BJT structure, a PN structure, a PIN structure, a heterogeneous PN structure, an IGBT structure, a GTO structure and an SJ structure.

[0055] In this embodiment, the electronic control unit is a JFET structure. Figure 5 The figure shows a schematic diagram of an electronic control unit, in which a JFET region is formed by two lateral back-to-back PN junctions, and P+ regions 9 are formed on both sides. The voltage on the gate metal 10 is controlled, and then the width of the PN junction depletion region is controlled to pinch off the conductive channel, thereby achieving a switch control effect.

[0056] Correspondingly, the above-mentioned JFET structure is realized by etching the Fin structure in the above-mentioned step S2, and then forming a P+ region 9 - a (quasi) P-type region on both sides of the Fin structure by ion implantation. The implanted ion source can be one or a combination of N and Mg ions.

[0057] For the rest of the same structures, please refer to the introduction of Example 1 and will not be repeated here.

[0058] Example 4 Based on Example 1 and Example 2, the difference is: The gallium oxide epitaxial layer (n--Ga 2 O 3 ) can also be one or any combination of wide bandgap semiconductor materials such as AlN, BN, SiC, GaN, diamond, etc., or a combination of any doping concentration and any doping type (P-type and N-type). The composite wafer voltage-resistant layer structure can be constructed by bonding the voltage-resistant layer using a vacuum bonding process.

[0059] In this embodiment, if Figure 6 As shown, the epitaxial layer is Ga 2 O 3 The combination is to use vacuum bonding process to bond the pressure-resistant layer and substrate peeling to construct a composite wafer pressure-resistant layer structure.

[0060] For the rest of the same structures, please refer to the introduction of Example 1 and will not be repeated here.

[0061] Example 5 Based on Example 1 and Example 2, the difference is: The groove structure in the light control unit can also be various regular or irregular groove structures. In this embodiment, for example Figure 7 As shown, it is a pentagonal groove; (quasi) P-type AZO thin film material (transparent thin film material), or N-type highly doped AZO (n+-AZO), so that this layer of film is connected with the n--Ga2 O 3 The voltage-resistant layer forms a built-in slowly varying electric field. Under this slowly varying electric field, a depletion region will also be generated when the electrons reach equilibrium. This depletion region also generates electron-hole pairs under light conditions. At the same time, under an external high voltage, an avalanche effect is generated, ultimately forming a high-voltage pulse current.

[0062] Based on the above pentagonal groove structure, the design of the substrate layer can be to form N-type heavy doping through ion implantation to form a good ohmic contact with the drain electrode, so that the forward conduction characteristics can be controlled and optimized, such as Figure 8 As shown in the figure, the green part below the gate metal of the electric control unit is the gate dielectric layer, which is generally 5-100nm Al 2 O 3 Or SiN, SiO 2 The gray part is SiO 2 etc. transparent dielectric passivation layer materials; optionally, the source electrode can extend out to form a metal field plate to achieve better reverse electric field shielding reliability for the electrical control unit.

[0063] In an optional example, N+ ion implantation is performed on the back side of the substrate layer to form good ohmic contact conduction characteristics with the back side drain metal.

[0064] For the rest of the same structures, please refer to the introduction of Example 1 and will not be repeated here.

[0065] Example 6 Based on Example 5, the difference is: like Fig. 9 and Fig.10 As shown, based on the above pentagonal groove structure, the design for the substrate layer can be: the substrate layer is P-type or quasi-P-type (such as P-NiO), forming a good contact with the drain electrode, and the cutoff and conduction of the device can be controlled from the back.

[0066] In an optional example, the back of the substrate is formed of a PN heterostructure with a P-type oxide and a substrate, thereby achieving better reverse control turn-off characteristics. The substrate material can be an N-type high-resistance or high-purity semi-insulating semiconductor material, or a P-type or quasi-P-type material, such as a 20-500um or even thicker gallium oxide semiconductor material, so that the entire substrate area can form a high electric field withstand voltage layer during reverse withstand voltage, thereby constructing an ultra-high withstand voltage switch.

[0067] For the rest of the same structures, please refer to the introduction of Example 1 and will not be repeated here.

[0068] In summary, the longitudinal light control unit and semiconductor voltage-resistant unit composite device and the corresponding manufacturing method provided in the above-mentioned embodiments 1 to 6 all have the following technical effects: First, a new type of gallium oxide light-controlled high-voltage and high-current power device was proposed for the first time by directly injecting photons into the body region of the wide-bandgap semiconductor material's voltage-resistant layer. This solution solves the problem of marketization of gallium oxide power devices in the absence of P-type doping in gallium oxide materials. That is, only n-type gallium oxide materials are used to realize ultra-high voltage and high-current power devices.

[0069] Second, the structural design of the combination of the electric control unit and the optical control unit that penetrates into the epitaxial region of the groove composite structure can allow the photogenerated carriers to penetrate into the high-voltage resistance body region inside the device structure, solving the problem that the electron-hole pairs formed by light irradiation on the surface of the material are quickly recombined by the multi-carriers in the neutral region, resulting in small conduction current and insensitive optical control; at the same time, the ultra-high voltage switching process can be controlled by a low-voltage electric control unit; When the light control unit that penetrates deep into the epitaxial body area adopts a multi-level groove structure, the multi-level groove auxiliary light injection area structure can penetrate deep into the epitaxial voltage-resistant layer, and even penetrate the epitaxial layer into the voltage-resistant high-resistance substrate layer, thereby achieving a deeper, high-light-injection-total-surface-area-ratio photon injection conductivity modulation area, which is beneficial to further reduce the on-resistance when the device is turned on by light.

[0070] Third, replace traditional silicon-based materials with wide-bandgap semiconductor voltage-resistant materials such as gallium oxide, and innovate structural design to fundamentally improve the physical limits of light-controlled power devices, give full play to the material properties, and manufacture light-controlled power devices that can work stably at higher temperatures, higher voltages, and in harsher environments, namely E c- Ga2O3 >E c- Si , T c- Ga2O3 >T c- Si .

[0071] In the description of this specification, the description with reference to the terms "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiments of the present invention. In this specification, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A composite device of a longitudinal light control unit and a semiconductor voltage-resistant unit, characterized in that: include: Substrate layer, n- epitaxial layer, n+ epitaxial layer, n++ epitaxial layer, voltage-resistant unit, electric control unit and light control unit; The n- epitaxial layer and the n+ epitaxial layer are sequentially stacked on the substrate layer from bottom to top; The voltage-resistant unit is formed by constructing the n-epitaxial layer and the n+epitaxial layer together with the substrate layer; the electric control unit and the light control unit are respectively arranged on the voltage-resistant unit; The electric control unit is formed by performing Si ion implantation on the n+ epitaxial layer to form the n++ epitaxial layer, and the n++ epitaxial layer and the ohmic metal form a source electrode; the gate dielectric / P+ region, the gate metal and the interlayer dielectric are respectively provided on both sides of the n++ epitaxial layer and the n+ epitaxial layer; The light control unit is formed by constructing a groove structure from the surface of the n+ epitaxial layer toward the substrate layer, forming a P-type thin film layer by a sputtering stripping process, the P-type thin film layer and the n+ epitaxial layer form a PN junction to form a local depletion region, and a light control electrode is provided on the inner wall side of the P-type thin film layer.

2. The composite device of the longitudinal light control unit and the semiconductor voltage-resistant unit according to claim 1, characterized in that: The material of the substrate layer is an N-type high-resistance or high-purity semi-insulating semiconductor material, or a P-type or quasi-P-type material.

3. The composite device of the longitudinal light control unit and the semiconductor withstand voltage unit according to claim 2, characterized in that: The composite device further includes a drain electrode; The drain electrode is arranged at the bottom of the substrate layer.

4. The composite device of the longitudinal light control unit and the semiconductor withstand voltage unit according to claim 1, characterized in that: The P-type thin film layer is made of transparent material.

5. The composite device of the longitudinal light control unit and the semiconductor voltage-resistant unit according to claim 1, characterized in that: The light-controlled electrode is a transparent metal layer.

6. The composite device of the vertical light control unit and the semiconductor withstand voltage unit according to claim 1, characterized in that: The groove structure is a multi-level groove, a regular groove or an irregular groove.

7. The composite device of the vertical light control unit and the semiconductor voltage-resistant unit according to claim 1, characterized in that: The electric control unit is provided with one of a Fin structure, a JFET structure, a GAA structure, a MOS structure, a BJT structure, a PN structure, a PIN structure, a heterogeneous PN structure, an IGBT structure, a GTO structure and an SJ structure.

8. The composite device of the vertical light control unit and the semiconductor withstand voltage unit according to claim 1, characterized in that: The n-epitaxial layer is one or any combination of Ga2O3, AlN, BN, SiC, GaN, and diamond wide bandgap semiconductor materials.

9. A method for manufacturing a composite device of a longitudinal light control unit and a semiconductor withstand voltage unit as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: S1: constructing a current channel layer on the substrate layer and the surface of the n- epitaxial wafer, and sequentially forming an n+ epitaxial layer and an n++ epitaxial layer by ion implantation; S2: etching the n+ epitaxial layer and the n++ epitaxial layer; S3: growing a gate dielectric layer and a gate metal layer in sequence at the edge of the etching; S4: Use photoresist planarization process to expose the top gate metal; S5: etching the gate metal and the gate dielectric in sequence on the structure after the photoresist is planarized, and performing a resist stripping process after etching; S6: growing an interlayer dielectric, and then etching the interlayer dielectric to open holes; S7: selectively depositing source metal locally by evaporation and stripping, and then annealing to form ohmic contact, and the electronic control unit is completed; S8: Protect the electric control unit by applying glue, and only expose and etch the light control unit accordingly; Etching the n+ epitaxial layer and the n++ epitaxial layer, and simultaneously adopting a sidewall process to obtain a trench structure; S9: growing a layer of transparent thin P-type material on the surface of the groove structure by a sputtering process to form a P-type thin film layer; S10: evaporating a transparent metal on the P-type thin film layer, so that the transparent P-type thin film layer forms a light-controlled electrode; The transparent metal and the transparent P-type thin film layer are annealed to form an ohmic contact; Flip the device over, evaporate metal on the substrate layer, and form an ohmic contact after annealing to manufacture the drain electrode.

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