Silicon-based electric pump laser and preparation method thereof

Abstract

The embodiment of the invention provides a silicon-based electric pump laser and a preparation method thereof, the silicon-based electric pump laser comprises an SOI substrate, the SOI substrate comprises a silicon top layer, a silicon dioxide landfill layer and a silicon bottom layer which are arranged from top to bottom, the silicon top layer is provided with a groove, the groove depth of the groove penetrates through the silicon top layer, and the silicon top layer is provided with an N-type doped region and a P-type doped region at two sides of the groove; the silicon dioxide isolation layer is filled in the groove; the light-emitting material waveguide is arranged above the silicon top layer and stretches across the groove, one end of the light-emitting material waveguide is in contact with the N-type doped region, the other end of the light-emitting material waveguide is in contact with the P-type doped region, and the light-emitting material waveguide is a single crystal formed by annealing, melting, cooling and transverse epitaxy; and the insulating layer is arranged above the silicon dioxide isolating layer and the luminescent material waveguide. According to the silicon-based electric pump laser provided by the embodiment of the invention, the material crystal quality and the carrier injection efficiency are effectively improved, and the optical loss of a device is reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of semiconductor lasers, and in particular to a silicon-based electrically pumped laser and a preparation method thereof. Background Art

[0002] As the integration of silicon integrated circuits becomes higher and higher, the speed of information transmission becomes faster and faster. Traditional electrical interconnection has shown its technical limitations. Optical interconnection has the characteristics of high speed, high bandwidth, and low power consumption. Therefore, people are eager to realize optical interconnection over short distances, especially silicon-based optical interconnection between chips and within chips. Using IV group materials to make silicon-based IV group lasers is one of the current research hotspots.

[0003] Germanium-tin material is a Group IV material compatible with CMOS technology. When the tin content reaches 6-9%, it can be transformed into a direct bandgap material, greatly improving the luminous efficiency of the material. However, there is a large lattice mismatch between germanium-tin material and silicon, and there is also a lack of lattice-matched optical confinement layer materials. Therefore, the current germanium-tin electrically pumped lasers have problems such as low crystal quality, too high lasing threshold, and too low operating temperature. Summary of the invention

[0004] The present disclosure provides a silicon-based electrically pumped laser and a method for preparing the same.

[0005] According to one aspect of an embodiment of the present disclosure, a silicon-based electrically pumped laser is provided, comprising: a silicon-based electrically pumped laser, comprising: an SOI substrate, the SOI substrate comprising a silicon top layer, a silicon dioxide buried layer and a silicon bottom layer arranged from top to bottom, the silicon top layer being provided with a groove, the groove depth of the groove penetrating the silicon top layer, the silicon top layer being provided with an N-type doping region and a P-type doping region on both sides of the groove; a silicon dioxide isolation layer, the silicon dioxide isolation layer filling the groove and covering the upper surface of the silicon top layer outside the N-type doping region and the P-type doping region; a light-emitting material waveguide, the light-emitting material waveguide being arranged on the upper surface of the silicon top layer and spanning the groove, one end of the light-emitting material waveguide being in contact with the N-type doping region, and the other end being in contact with the P-type doping region to form an electrical connection; the light-emitting material waveguide being a single crystal formed by annealing, melting, cooling and lateral epitaxy; an insulating layer, the insulating layer being arranged above the silicon dioxide isolation layer and the light-emitting material waveguide.

[0006] According to the embodiment of the present disclosure, the light emitting material waveguide contacts the upper surface of the silicon top layer outside the N-type doping region and the P-type doping region, so that the silicon top layer can serve as a seed crystal for lateral epitaxy of the light emitting material waveguide by annealing, melting, cooling.

[0007] According to an embodiment of the present disclosure, the SOI substrate is provided with a channel penetrating the silicon top layer and the silicon dioxide buried layer, the channel is far away from the N-type doped region and the P-type doped region, and the light-emitting material waveguide contacts the silicon bottom layer through the channel, so that the silicon bottom layer can serve as a seed crystal for annealing, melt cooling and lateral epitaxy of the light-emitting material waveguide.

[0008] According to the embodiment of the present disclosure, it also includes a P electrode and an N electrode; the insulating layer includes a silicon dioxide capping layer and an insulating dielectric layer, the silicon dioxide capping layer is arranged on the upper surface of the silicon dioxide isolation layer, and the insulating dielectric layer is arranged on the silicon dioxide capping layer, the light-emitting material waveguide and the upper surface of the silicon top layer; the insulating dielectric layer is provided with electrode windows at positions opposite to the N-type doping region and the P-type doping region, respectively, and the P electrode and the N electrode respectively achieve ohmic contact with the P-type doping region and the N-type doping region through the electrode windows.

[0009] According to an embodiment of the present disclosure, the light emitting material waveguide is germanium-tin alloy or pure germanium or InGaAs material.

[0010] According to another aspect of the embodiment of the present disclosure, a method for preparing a silicon-based electrically pumped laser is also provided, comprising: making a groove on the silicon top layer of an SOI substrate, and making an N-type doped region and a P-type doped region on both sides of the groove; making a silicon dioxide isolation layer on the silicon top layer; the silicon dioxide isolation layer fills the groove and covers the N-type doped region and the P-type doped region, and the silicon dioxide isolation layer is provided with a window exposing the SOI substrate; making a light-emitting material waveguide on the silicon dioxide isolation layer; annealing, melting and cooling the light-emitting material waveguide, and laterally epitaxying to form a single crystal; and removing the silicon dioxide isolation layer so that the light-emitting material waveguide contacts the N-type doped region and the P-type doped region.

[0011] According to an embodiment of the present disclosure, fabricating a light-emitting material waveguide on a silicon dioxide isolation layer further includes: fabricating a silicon dioxide capping layer on the light-emitting material waveguide; the silicon dioxide capping layer is used to wrap the light-emitting material waveguide together with the silicon dioxide isolation layer during the process of annealing, melting, cooling, and lateral epitaxy of the light-emitting material waveguide to form a single crystal; the method further includes removing the silicon dioxide capping layer to expose the light-emitting material waveguide and the silicon top layer.

[0012] According to an embodiment of the present disclosure, the method also includes: forming an insulating dielectric layer on the light-emitting material waveguide, the insulating dielectric layer covering the silicon top layer and the light-emitting material waveguide; opening an electrode window on the insulating dielectric layer to expose the N-type doped region and the P-type doped region; forming an N electrode and a P electrode, the N electrode and the P electrode are ohmically connected to the N-type doped region and the P-type doped region respectively through the electrode window.

[0013] According to the embodiment of the present disclosure, the light-emitting material waveguide contacts the silicon top layer through the window; the light-emitting material waveguide is annealed, melt-cooled, and laterally epitaxially formed into a single crystal, including: annealing, melt-cooling the light-emitting material waveguide, and annealing, melt-cooling, and laterally epitaxially forming a single crystal using the silicon top layer as a seed crystal.

[0014] According to the embodiment of the present disclosure, the SOI substrate is provided with a channel penetrating the silicon top layer and the silicon dioxide buried layer of the SOI substrate, and the light-emitting material waveguide contacts the silicon bottom layer of the SOI substrate through the window and the channel; the light-emitting material waveguide is annealed, melt-cooled, and laterally epitaxially formed into a single crystal, including: annealing, melt-cooling the light-emitting material waveguide, and annealing, melt-cooling, and laterally epitaxially forming a single crystal using the silicon bottom layer as a seed crystal. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above contents and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0016] Figure 1 is a schematic diagram of the cross-sectional structure of a silicon-based electrically pumped laser according to an embodiment of the present disclosure;

[0017] Figure 2 is a schematic diagram of a side cross-sectional structure of a silicon-based electrically pumped laser during the preparation process according to an embodiment of the present disclosure;

[0018] Figure 3 is a schematic diagram of a front cross-sectional structure of a silicon-based electrically pumped laser during the preparation process according to an embodiment of the present disclosure;

[0019] Figure 4 It is a schematic flow chart of a method for preparing a silicon-based electrically pumped laser according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0020] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0021] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0022] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0023] When using expressions such as "at least one of A, B, and C, etc.", they should generally be interpreted according to the meaning of the expression commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0024] In the technical solution of the present disclosure, the collection, storage, use, processing, transmission, provision, disclosure and application of the data involved (including but not limited to user personal information) comply with the provisions of relevant laws and regulations, take necessary confidentiality measures, and do not violate public order and good morals.

[0025] In the technical solution of the present disclosure, before obtaining or collecting relevant data, the authorization or consent of the data owner is obtained.

[0026] The embodiment of the present disclosure provides a silicon-based electrically pumped laser, including an SOI substrate 100, a silicon dioxide isolation layer 200, a light-emitting material waveguide 300 and an insulating layer. The SOI substrate 100 includes a silicon top layer 110, a silicon dioxide buried layer 120 and a silicon bottom layer 130 arranged from top to bottom. The silicon top layer 110 is provided with a groove 113, the groove depth of the groove 113 runs through the silicon top layer 110, and the silicon top layer 110 is provided with an N-type doping region 112 and a P-type doping region 111 on both sides of the groove 113. The silicon dioxide isolation layer 200 fills the groove 113 and covers the upper surface of the silicon top layer 110 outside the P-type doping region 111 and the N-type doping region 112. The light-emitting material waveguide 300 is arranged above the silicon top layer 110 and across the groove 113. One end of the light-emitting material waveguide 300 contacts the N-type doping region 112, and the other end contacts the P-type doping region 111 to form an electrical connection. The light-emitting material waveguide 300 is a single crystal formed by annealing, melting, cooling, and lateral epitaxy. An insulating layer is arranged above the silicon dioxide isolation layer 200 and the light-emitting material waveguide 300.

[0027] The silicon top layer 110 is a lightly doped or intrinsic material with a resistivity greater than 1 ohm / cm. The P-type doped region 111 and the N-type doped region 112 need to achieve excellent ohmic contact, and their doping concentration is usually required to be greater than 5×10 18 / cm 3 .

[0028] like Figure 1As shown, the silicon dioxide isolation layer 200 is arranged on the upper surface of the silicon top layer 110, filling the groove 113 until the upper surface of the silicon top layer 110 is flat, and is provided with an opening exposing the N-type doped region 112 and the P-type doped region 111. The light-emitting material waveguide 300 is arranged on the silicon top layer 110, located in the opening of the silicon dioxide isolation layer 200, spanning the groove 113, and the two ends are respectively in contact with the two doped regions, so that the P-type doped region 111, the light-emitting material waveguide 300 and the N-type doped region 112 form a lateral PIN electrical injection structure. Since the groove 113 separates the two doped regions and the silicon dioxide isolation layer 200 is filled in the groove 113, the diffusion of carriers in the silicon top layer 110 is avoided, and the injection efficiency of carriers into the light-emitting material waveguide 300 is effectively improved.

[0029] The silicon-based electrically pumped laser provided in the embodiment of the present disclosure forms a lateral PIN electrical injection structure for the light-emitting material waveguide 300, and does not require the optical confinement layer required by the traditional longitudinal PIN electrical injection structure, thereby avoiding the problem that the traditional silicon-based germanium-tin electrically pumped laser uses a lattice-mismatched optical confinement cap layer to provide optical confinement and carrier injection, resulting in weak luminescence, poor quality, and high optical resonant cavity loss of the germanium-tin material; and the light-emitting material waveguide 300 is a single crystal material formed by annealing, melt cooling, and lateral epitaxy, which meets the requirements for high tin component, high crystal quality, and strain relaxation of the germanium-tin waveguide material.

[0030] According to an embodiment of the present disclosure, the light emitting material waveguide 300 contacts the upper surface of the silicon top layer 110 outside the N-type doping region 112 and the P-type doping region 111, so that the silicon top layer 110 can serve as a seed crystal for annealing, melting, cooling and lateral epitaxy of the light emitting material waveguide 300. In another embodiment, the SO1 substrate 100 is provided with a channel penetrating the silicon top layer 110 and the silicon dioxide buried layer 120, the channel being away from the N-type doping region 112 and the P-type doping region 111, and the light emitting material waveguide 300 contacts the silicon bottom layer 130 through the channel, so that the silicon bottom layer 130 can serve as a seed crystal for annealing, melting, cooling and lateral epitaxy of the light emitting material waveguide 300.

[0031] It is worth noting that in the preparation process of the silicon-based electrically pumped laser of the embodiment of the present disclosure, Figure 2 and Figure 3 As shown, the silicon dioxide isolation layer 200 is first deposited on the upper surface of the silicon top layer 110 to cover the N-type doping region 112 and the P-type doping region 111 , and the silicon dioxide isolation layer 200 is provided with a window 201 away from the two doping regions, through which the silicon top layer 110 is exposed.

[0032] The light emitting material waveguide 300 is firstly fabricated on the silicon dioxide isolation layer 200. On one hand, the light emitting material waveguide 300 is separated from the two doped regions by the silicon dioxide isolation layer 200. On the other hand, the light emitting material waveguide 300 extends to the window 201 and contacts the silicon top layer 110 through the window 201. Alternatively, in another embodiment, the SOI substrate 100 is further provided with a channel penetrating the silicon top layer 110 and the silicon dioxide buried layer 120, the channel is butted with the window 201, and the light emitting material waveguide 300 extends to the window 201 and contacts the silicon bottom layer 130 through the window 201 and the channel.

[0033] Therefore, during the annealing, melting and cooling process of the light emitting material waveguide 300, the light emitting material waveguide 300 can be epitaxially formed into a single crystal with the contacted silicon top layer 110 or silicon bottom layer 130 as a seed crystal. After the single crystal is formed, the portion of the silicon dioxide isolation layer 200 covering the two doped regions and located below the light emitting material waveguide 300 is correspondingly removed, so that the light emitting material waveguide 300 is aligned and falls into the two doped regions, forming a lateral PIN electrical injection structure.

[0034] In the silicon-based electrically pumped laser provided by the embodiment of the present disclosure, the light-emitting material waveguide 300 uses the silicon bottom layer 130 or the silicon top layer 110 as a seed crystal, and is annealed, melted, cooled, and laterally epitaxially formed into a single crystal. In the process of forming the single crystal, the silicon dioxide isolation layer 200 is isolated from the silicon top layer 110, especially from the large-area contact with the two doped regions, so that the light-emitting material waveguide 300 can be completely relaxed, lattice mismatch can be avoided, and the requirements for high tin component, high crystal quality and strain relaxation of the germanium-tin waveguide material can be fully met.

[0035] According to an embodiment of the present disclosure, the insulating layer includes a silicon dioxide capping layer 400 and an insulating dielectric layer 500 . The silicon dioxide capping layer 400 is disposed on the upper surface of the silicon dioxide isolation layer 200 , and the insulating dielectric layer 500 is disposed on the upper surfaces of the silicon dioxide capping layer 400 , the light-emitting material waveguide 300 and the silicon top layer 110 .

[0036] It is worth noting that, in the preparation process of the silicon-based electrically pumped laser provided in the embodiment of the present disclosure, before the luminescent material waveguide 300 is annealed, a silicon dioxide cap layer 400 is firstly formed on the surface of the luminescent material waveguide 300 and the silicon dioxide isolation layer 200, so as to Figure 2 and Figure 3 As shown, the silicon dioxide cap layer 400 and the silicon dioxide isolation layer 200 together wrap the light emitting material waveguide 300, and during the annealing process, the air can be isolated, the agglomeration and evaporation of the molten material can be suppressed, and the light emitting material waveguide 300 maintains structural integrity. After the single crystal is formed, the silicon dioxide cap layer 400 and the silicon dioxide isolation layer 200 are removed accordingly, so that the light emitting material waveguide 300 and the silicon top layer 110 are exposed. Figure 1Then, an insulating dielectric layer 500 is deposited to cover the light emitting material waveguide 300 and the silicon top layer 110 .

[0037] Furthermore, according to an embodiment of the present disclosure, the silicon-based electrically pumped laser also includes a P-electrode 610 and an N-electrode 620; the insulating dielectric layer 500 is provided with an electrode window at a position opposite to the N-type doping region 112 and the P-type doping region 111, and the P-electrode 610 and the N-electrode 620 respectively achieve ohmic contact with the P-type doping region 111 and the N-type doping region 112 through the electrode windows.

[0038] like Figure 1 As shown, electrode windows can be formed at corresponding positions where the insulating dielectric layer 500 contacts the two doped regions by dry etching, and the P electrode 610 and the N electrode 620 are respectively installed in the corresponding electrode windows to form ohmic contacts with the corresponding doped regions. Under the function of the electrode, the doped region injects carriers into the light-emitting material waveguide 300 to form electric pumping. Since the P electrode 610 and the N electrode 620 are both far away from the light-emitting material waveguide 300 and insulated and separated by the insulating dielectric layer 500, the optical loss of the device can be effectively reduced, thereby realizing a low-threshold silicon-based electrically pumped laser.

[0039] According to an embodiment of the present disclosure, the light emitting material waveguide 300 is a germanium-tin alloy or pure germanium or InGaAs material.

[0040] On the other hand, Figure 4 As shown, the embodiment of the present disclosure also provides a method for preparing a silicon-based electrically pumped laser, comprising steps S1 to S5:

[0041] S1 , forming a groove 113 in the silicon top layer 110 of the SOI substrate 100 , and forming an N-type doping region 112 and a P-type doping region 111 on both sides of the groove 113 .

[0042] According to the embodiment of the present disclosure, the thickness of the silicon top layer 110 is 220nm, the crystal orientation is (001), the conductivity type is P type, and the resistivity is 10 ohms / cm. The thickness of the silicon dioxide buried layer 120 is 2μm. The silicon top layer 110 is photolithographically and dry-etched to form a groove 113, the depth of the groove 113 is 220nm, and the width is 100-400nm. The N-type doping region 112 and the P-type doping region 111 are made by ion implantation or impurity diffusion. The doping concentration of the two doping regions is 1×10 19 / cm 3 -1×10 20 / cm 3 , the doping depth is less than 150nm.

[0043] S2 , forming a silicon dioxide isolation layer 200 on the silicon top layer 110 ; the silicon dioxide isolation layer 200 fills the groove 113 and covers the N-type doping region 112 and the P-type doping region 111 , and is provided with a window 201 exposing the silicon top layer 110 .

[0044] According to the embodiment of the present disclosure, the silicon dioxide isolation layer 200 may be deposited by plasma enhanced chemical vapor deposition with a thickness of 200-500 nm. Chemical mechanical polishing may be used to improve the flatness of the narrow groove.

[0045] S3 , manufacturing a light emitting material waveguide 300 on the silicon dioxide isolation layer 200 .

[0046] According to the embodiments of the present disclosure, the light-emitting material can be deposited on the silicon dioxide isolation layer 200 and the window 201 by magnetron sputtering, molecular beam epitaxy or chemical vapor deposition, and the light-emitting material waveguide 300 is formed by etching. In this state, the light-emitting material waveguide 300 is in an amorphous, polycrystalline or microcrystalline state, and the length (e.g. Figure 2 direction) is 50-300μm, and the width (as shown Figure 3 The diameter of the nanostructured carbon fiber (in the direction shown) is 1-3 μm and the thickness is 400-800 nm.

[0047] The light-emitting material waveguide 300 in an amorphous, polycrystalline or microcrystalline state contacts the silicon top layer 110 through the window 201. Alternatively, in another embodiment, the SOI substrate 100 is provided with a channel penetrating the silicon top layer 110 and the silicon dioxide buried layer 120, and the channel is connected to the window 201. The light-emitting material waveguide 300 in an amorphous, polycrystalline or microcrystalline state contacts the silicon bottom layer 130 through the window 201 and the channel.

[0048] S4, annealing and melting the light emitting material waveguide 300 to form a single crystal by lateral epitaxy.

[0049] According to the embodiments of the present disclosure, the light emitting material waveguide 300 is heated to above the melting point by rapid thermal annealing or laser thermal annealing to melt it, and then cooled down after being maintained for a few seconds. During cooling, a single crystal is formed by lateral epitaxy with the silicon top layer 110 or the silicon bottom layer 130 as a seed crystal, thereby meeting the requirements of high crystal quality and complete relaxation.

[0050] S5 , removing the silicon dioxide isolation layer 200 , so that the light emitting material waveguide 300 contacts the N-type doping region 112 and the P-type doping region 111 .

[0051] According to the embodiment of the present disclosure, an etching method is adopted, and a photoresist is used as a mask, and a diluted hydrofluoric acid solution is used to selectively wet-etch and remove the silicon dioxide isolation layer 200 below and around the light-emitting material waveguide 300. After the wafer is taken out of the liquid, the light-emitting material waveguide 300 will naturally align and fall on both sides of the groove 113, forming a lateral PIN electrical injection structure with the N-type doping region 112 and the P-type doping region 111.

[0052] The method for preparing a silicon-based electrically pumped laser provided by the embodiment of the present disclosure can prepare a laser with a lateral PIN electrical injection structure, avoid the need for an optical confinement layer required by a conventional longitudinal PIN electrical injection structure, and avoid the problem that a conventional silicon-based germanium-tin electrically pumped laser uses a lattice-mismatched optical confinement cap layer to provide optical confinement and carrier injection, which results in weak luminescence, poor quality, and high optical resonant cavity loss of the germanium-tin material. The luminescent material waveguide 300 is a single crystal formed by annealing, melting, cooling, and lateral epitaxy. During the formation of the single crystal, the silicon top layer 110 or the silicon bottom layer 130 is used as a seed crystal, and the silicon dioxide isolation layer 200 separates it from the large-area contact with the silicon top layer 110, thereby avoiding the material quality problem caused by the introduction of the waveguide by conventional chemical vapor deposition or molecular beam epitaxy, and meeting the requirements for high tin component, high crystal quality, and strain relaxation of the germanium-tin waveguide material.

[0053] According to an embodiment of the present disclosure, step S3 further includes: forming a silicon dioxide capping layer 400 on the light emitting material waveguide 300. Step S5 further includes removing the silicon dioxide capping layer 400 to expose the light emitting material waveguide 300 and the silicon top layer 110. The silicon dioxide capping layer 400 is used to wrap the light emitting material waveguide 300 together with the silicon dioxide isolation layer 200 during step S4.

[0054] According to the embodiment of the present disclosure, in step S3, after the light emitting material waveguide 300 is manufactured, a silicon dioxide capping layer 400 with a thickness of 400-800 nm is deposited on the light emitting material waveguide 300, the silicon dioxide isolation layer 200 and the silicon top layer 110 by plasma enhanced chemical vapor deposition. Then, during the annealing and melting process of the light emitting material waveguide 300, the silicon dioxide isolation layer 200 and the silicon dioxide capping layer 400 together wrap the light emitting material waveguide 300, which helps to isolate the air, suppress the agglomeration and evaporation of the molten material, and keep the structural integrity of the light emitting material waveguide 300.

[0055] After the single crystal is formed, similar to removing the silicon dioxide isolation layer 200, an etching method is adopted, using a photoresist as a mask, and a diluted hydrofluoric acid solution is used to selectively wet-etch and remove the silicon dioxide cap layer 400 around the light emitting material waveguide 300. Figure 1As shown, the first portion of the remaining silicon dioxide isolation layer 200 after processing fills the groove 113 , the second portion covers the surface of the silicon top layer 110 outside the two doping regions, and the silicon dioxide capping layer 400 covers the upper surface of the second portion of the silicon dioxide isolation layer 200 .

[0056] According to an embodiment of the present disclosure, the method for preparing a silicon-based electrically pumped laser further includes steps S6 to S8.

[0057] S6 , manufacturing an insulating dielectric layer 500 on the light emitting material waveguide 300 , wherein the insulating dielectric layer 500 covers the silicon top layer 110 and the light emitting material waveguide 300 .

[0058] According to an embodiment of the present disclosure, the insulating dielectric layer 500 is deposited by plasma enhanced chemical vapor deposition. The insulating dielectric layer 500 may be silicon dioxide or silicon nitride, and has a thickness of 300-1000 nm.

[0059] S7 , opening an electrode window on the insulating dielectric layer 500 to expose the N-type doping region 112 and the P-type doping region 111 .

[0060] According to the embodiment of the present disclosure, electrode windows are opened in the insulating dielectric layer 500 at positions corresponding to the N-type doping region 112 and the P-type doping region 111 by dry etching using a photoresist as a mask.

[0061] S8, manufacturing an N-electrode 620 and a P-electrode 610, wherein the N-electrode 620 and the P-electrode 610 are ohmically connected to the N-type doping region 112 and the P-type doping region 111 respectively through electrode windows.

[0062] According to the embodiments of the present disclosure, the doped region forms an electrical connection with the electrode ohmic contact, injects carriers into the light-emitting material waveguide 300, and forms electrical pumping. Since the P electrode 610 and the N electrode 620 are both far away from the light-emitting material waveguide 300 and insulated and separated by the insulating dielectric layer 500, the optical loss of the device can be effectively reduced, thereby realizing a low-threshold silicon-based electrically pumped laser. By etching or cleaving, the light-emitting material waveguide 300 is cut off at a suitable position, and the resonant cavity surfaces are made at both ends to form a waveguide resonant cavity, completing the laser preparation.

[0063] According to the above embodiments, an embodiment of the present disclosure provides a method for preparing a silicon-based electrically pumped laser, comprising the steps of:

[0064] S1, forming a groove 113 in the silicon top layer 110 of the SOI substrate 100, and forming an N-type doping region 112 and a P-type doping region 111 on both sides of the groove 113;

[0065] S2, forming a silicon dioxide isolation layer 200 on the silicon top layer 110; the silicon dioxide isolation layer 200 fills the groove 113 and covers the N-type doping region 112 and the P-type doping region 111;

[0066] S3, manufacturing a light emitting material waveguide 300 on the silicon dioxide isolation layer 200, and manufacturing a silicon dioxide cap layer 400 on the light emitting material waveguide 300;

[0067] S4, annealing and melting the light emitting material waveguide 300 to form a single crystal by lateral epitaxy;

[0068] S5, removing the portion of the silicon dioxide isolation layer 200 between the light emitting material waveguide 300 and the silicon top layer 110, so that the light emitting material waveguide 300 contacts the N-type doping region 112 and the P-type doping region 111; removing the silicon dioxide capping layer 400, so as to expose the light emitting material waveguide 300 and the silicon top layer 110;

[0069] S6, manufacturing an insulating dielectric layer 500 on the light emitting material waveguide 300, wherein the insulating dielectric layer 500 covers the silicon top layer 110 and the light emitting material waveguide 300;

[0070] S7, opening an electrode window on the insulating dielectric layer 500 to expose the N-type doping region 112 and the P-type doping region 111;

[0071] S8, manufacturing an N-electrode 620 and a P-electrode 610, wherein the N-electrode 620 and the P-electrode 610 are ohmically connected to the N-type doping region 112 and the P-type doping region 111 respectively through electrode windows.

[0072] It is worth noting that the method for preparing a silicon-based electrically pumped laser provided in the embodiment of the present disclosure does not require subsequent process manufacturing of the light-emitting material waveguide 300, and therefore Group III-V materials can also be used as light-emitting materials to manufacture silicon-based Group III-V lasers, thereby improving their compatibility with silicon CMOS processes.

[0073] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways, even if such combinations and / or combinations are not explicitly described in the present disclosure. In particular, the features described in the various embodiments and / or claims of the present disclosure may be combined and / or combined in a variety of ways without departing from the spirit and teachings of the present disclosure. All of these combinations and / or combinations fall within the scope of the present disclosure.

[0074] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A silicon-based electrically pumped laser, characterized in that: include: An SOI substrate, wherein the SOI substrate comprises a silicon top layer, a silicon dioxide buried layer and a silicon bottom layer arranged from top to bottom, the silicon top layer is provided with a groove, the groove depth of the groove runs through the silicon top layer, and the silicon top layer is provided with an N-type doping region and a P-type doping region on both sides of the groove; A silicon dioxide isolation layer, the silicon dioxide isolation layer fills the groove and covers the upper surface of the silicon top layer outside the N-type doping region and the P-type doping region; A light-emitting material waveguide, the light-emitting material waveguide is arranged on the upper surface of the silicon top layer and spans the groove, one end of the light-emitting material waveguide contacts the N-type doping region, and the other end contacts the P-type doping region to form an electrical connection; the light-emitting material waveguide is a single crystal formed by annealing, melting, cooling and lateral epitaxy; An insulating layer is disposed above the silicon dioxide isolation layer and the light emitting material waveguide.

2. The silicon-based electrically pumped laser according to claim 1, characterized in that: The light emitting material waveguide contacts the upper surface of the silicon top layer outside the N-type doping region and the P-type doping region, so that the silicon top layer can serve as a seed crystal for annealing, melting, cooling and lateral epitaxy of the light emitting material waveguide.

3. The silicon-based electrically pumped laser according to claim 1, characterized in that: The SOI substrate is provided with a channel penetrating the silicon top layer and the silicon dioxide buried layer, the channel is far away from the N-type doped region and the P-type doped region, the light-emitting material waveguide contacts the silicon bottom layer through the channel, so that the silicon bottom layer can serve as a seed crystal for annealing, melt cooling and lateral epitaxy of the light-emitting material waveguide.

4. The silicon-based electrically pumped laser according to claim 1, characterized in that: Also includes a P electrode and an N electrode; The insulating layer comprises a silicon dioxide cap layer and an insulating dielectric layer, wherein the silicon dioxide cap layer is disposed on the upper surface of the silicon dioxide isolation layer, and the insulating dielectric layer is disposed on the upper surfaces of the silicon dioxide cap layer, the light emitting material waveguide and the silicon top layer; The insulating dielectric layer is provided with electrode windows at positions opposite to the N-type doping region and the P-type doping region, respectively, and the P electrode and the N electrode respectively achieve ohmic contact with the P-type doping region and the N-type doping region through the electrode windows.

5. The silicon-based electrically pumped laser according to claim 1, characterized in that: The light emitting material waveguide is germanium-tin alloy or pure germanium or InGaAs material.

6. A method for preparing a silicon-based electrically pumped laser, characterized in that: include: Making a groove on the silicon top layer of the SOI substrate, and making an N-type doped region and a P-type doped region on both sides of the groove; A silicon dioxide isolation layer is formed on the silicon top layer; the silicon dioxide isolation layer fills the groove and covers the N-type doping area and the P-type doping area, and the silicon dioxide isolation layer is provided with a window exposing the SOI substrate; Fabricating a light emitting material waveguide on the silicon dioxide isolation layer; Annealing, melting and cooling the light emitting material waveguide to form a single crystal by lateral epitaxy; The silicon dioxide isolation layer is removed so that the light emitting material waveguide contacts the N-type doping region and the P-type doping region.

7. The method for preparing a silicon-based electrically pumped laser according to claim 6, characterized in that: The step of fabricating a light emitting material waveguide on the silicon dioxide isolation layer further comprises: forming a silicon dioxide capping layer on the light emitting material waveguide; The silicon dioxide capping layer is used to wrap the light emitting material waveguide together with the silicon dioxide isolation layer in the process of annealing, melting, cooling, and lateral epitaxy to form a single crystal on the light emitting material waveguide; The method also includes removing the silicon dioxide capping layer to expose the light emitting material waveguide and the silicon top layer.

8. The method for preparing a silicon-based electrically pumped laser according to claim 7, characterized in that: The method further comprises: Making an insulating dielectric layer on the light-emitting material waveguide, wherein the insulating dielectric layer covers the silicon top layer and the light-emitting material waveguide; Opening an electrode window on the insulating dielectric layer to expose the N-type doping region and the P-type doping region; An N electrode and a P electrode are manufactured, and the N electrode and the P electrode are ohmically connected to the N-type doping region and the P-type doping region respectively through the electrode window.

9. The method for preparing a silicon-based electrically pumped laser according to claim 6, characterized in that: The light emitting material waveguide contacts the silicon top layer through the window; The annealing, melting and cooling of the light emitting material waveguide and the lateral epitaxy to form a single crystal comprises: annealing, melting and cooling of the light emitting material waveguide and the annealing, melting and cooling of the silicon top layer as a seed crystal and the lateral epitaxy to form a single crystal.

10. The method for preparing a silicon-based electrically pumped laser according to claim 6, characterized in that: The SOI substrate is provided with a channel penetrating the silicon top layer and the silicon dioxide buried layer of the SOI substrate, and the light emitting material waveguide contacts the silicon bottom layer of the SOI substrate through the window and the channel; The annealing, melting and cooling of the light emitting material waveguide and the lateral epitaxy to form a single crystal comprises: annealing, melting and cooling of the light emitting material waveguide and the annealing, melting and cooling of the silicon bottom layer as a seed crystal and the lateral epitaxy to form a single crystal.

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