CN111146681A

CN111146681A - SiC-based InP photonic integrated module and preparation method thereof

Info

Publication number: CN111146681A
Application number: CN201911320620.2A
Authority: CN
Inventors: 欧欣; 林家杰; 沈正皓; 金婷婷; 游天桂
Original assignee: Shanghai Institute of Microsystem and Information Technology of CAS
Current assignee: Shanghai Institute of Microsystem and Information Technology of CAS
Priority date: 2019-12-19
Filing date: 2019-12-19
Publication date: 2020-05-12
Anticipated expiration: 2039-12-19
Also published as: CN111146681B

Abstract

The application provides a preparation method of a SiC-based InP photonic integrated module, which comprises the following steps: obtaining a monocrystalline SiC substrate layer; preparing an Fe-doped InP thin film layer on the monocrystal SiC substrate layer to form a heterogeneous substrate; preparing a waveguide layer and an active layer in sequence on a heterogeneous substrate by adopting a heteroepitaxial growth method; carrying out grating etching on the active layer and preparing an electrode contact layer on the active layer; etching the waveguide layer, the active layer and the electrode contact layer to prepare a distributed feedback laser and prepare any one of an amplifier and a modulator; sequentially preparing a waveguide contact layer and a detector structure on the Fe-doped InP thin film layer by adopting a selective area epitaxy method; and etching the detector structure to prepare the detector. In the preparation method of the SiC-based InP photonic integrated module provided in the embodiment of the present application, InP is combined with a SiC-based substrate, so that a low thermal resistance and low mismatch SiC-based InP photonic integrated module is prepared.

Description

SiC-based InP photonic integrated module and preparation method thereof

Technical Field

The application relates to the technical field of photonic integration, in particular to a SiC-based InP photonic integrated module and a preparation method thereof.

Background

With the rapid development of information communication, the data volume is increased explosively, and photonic communication is favored due to its large bandwidth and high transmission speed. Over the past few decades, photonic integration techniques have been rapidly evolving from long-haul fiber optic communications, to the optical interconnects of short-haul data centers today, and to the use of optical interconnects instead of copper interconnects.

The InP-based photonic integration platform is a mature all-optical integrated platform at present, and can realize integration of various passive and active photonic devices, including lasers, modulators, detectors and the like. However, the InP photonic integrated platform uses InP as a waveguide, the difference between the refractive indices of the core layer and the cladding layer of the waveguide is too small to limit the light, and the refractive index difference between Si and SiO2 is large, which results in the size of the InP-based photonic integrated chip being much larger than that of the silicon photonic chip. If the InP photonic integration is combined with the SiO2/Si substrate, namely the InP photonic integration is realized on the InP/SiO2/Si foreign substrate, high-limit optical waveguide can be realized, and the size of a photonic chip is reduced. However, since the SiO2 layer has extremely low thermal conductivity, the temperature of the prepared device is very easy to rise during operation, and the output power and density of the device, especially a laser, are limited. And large thermal mismatch exists between InP and Si, and large thermal stress is introduced at high temperature in the device preparation process, so that the performance and the service life of the device are reduced.

Disclosure of Invention

The method solves the technical problems that the preparation process of the existing photonic integrated device is complex and difficult to control, and the output power and the density of the device are limited by low thermal conductivity.

In order to solve the technical problem, the embodiment of the application discloses a preparation method of a SiC-based InP photonic integrated module, which comprises the following steps:

obtaining a monocrystalline SiC substrate layer;

preparing an Fe-doped InP thin film layer on the monocrystal SiC substrate layer to form a heterogeneous substrate;

preparing a waveguide layer and an active layer in sequence on a heterogeneous substrate by adopting a heteroepitaxial growth method;

carrying out grating etching on the active layer and preparing an electrode contact layer on the active layer;

etching the waveguide layer, the active layer and the electrode contact layer to prepare a distributed feedback laser and prepare any one of an amplifier and a modulator, wherein the distributed feedback laser and the amplifier or the modulator share the same active layer;

sequentially preparing a waveguide contact layer and a detector structure on the Fe-doped InP thin film layer by adopting a selective area epitaxy method;

and etching the detector structure to prepare the detector.

Further, preparing the Fe-doped InP thin film layer on the monocrystalline SiC substrate layer specifically comprises the following steps:

bonding and connecting the single crystal SiC substrate layer with the Fe-doped InP layer;

and preparing the Fe-doped InP thin film layer on the monocrystalline SiC substrate layer by an ion beam stripping technology or an etching thinning technology.

Further, the thickness of the Fe-doped InP thin film layer is 100nm-1 um.

Further, the heteroepitaxial growth method includes a molecular beam epitaxial growth method or a chemical vapor phase epitaxial growth method.

Further, the waveguide layer includes a single waveguide layer, a dual waveguide layer, or a quantum well hybrid waveguide layer.

Further, the active layer includes a barrier layer.

Further, the grating etching method includes a dry etching method or a wet etching method.

The embodiment of the application also discloses a SiC-based InP photonic integrated module, which is prepared by the preparation method and comprises the following steps: the device comprises a single crystal SiC substrate layer, an Fe-doped InP thin film layer, an amplifier/modulator, a distributed feedback laser and a detector;

the Fe-doped InP thin film layer and the single crystal SiC substrate layer are connected to form a heterogeneous substrate;

the amplifier/modulator, distributed feedback laser and detector are integrated on a foreign substrate.

Furthermore, the connection mode of the Fe-doped InP thin film layer and the single crystal SiC substrate layer is bonding connection.

By adopting the technical scheme, the application has the following beneficial effects:

in the preparation method of the SiC-based InP photonic integrated module provided in the embodiment of the present application, InP is combined with a SiC-based substrate, and a low thermal resistance and low mismatch SiC-based InP photonic integrated module is prepared by using the properties that SiC has high thermal conductivity and a certain refractive index difference with an InP thin film, and the thermal expansion coefficient is close to that of InP in a direction perpendicular to the C axis.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a flowchart of a method for manufacturing a SiC-based InP photonic integrated module according to an embodiment of the present application;

fig. 2 is a schematic partial flow chart of a method for manufacturing a SiC-based InP photonic integrated module according to an embodiment of the present application;

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic may be included in at least one implementation of the present application. In the description of the embodiments of the present application, it is to be understood that the terms "upper", "lower", "top", "bottom", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present application and simplifying the description, and do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Moreover, the terms "first," "second," and the like are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in sequences other than those illustrated or described herein.

Referring to fig. 1, fig. 1 is a schematic flow chart of a method for manufacturing a SiC-based InP photonic integrated module according to an embodiment of the present disclosure, where the method includes the following steps:

s1, obtaining a monocrystalline SiC substrate layer; wherein the single crystal SiC substrate can be a single crystal 6H-SiC or 4H-SiC substrate.

S2, preparing an Fe-doped InP thin film layer on the monocrystalline SiC substrate layer to form a heterogeneous substrate; the method specifically comprises the following steps: firstly, bonding and connecting a monocrystal SiC substrate layer with an Fe-doped InP layer; and then preparing the Fe-doped InP thin film layer on the monocrystalline SiC substrate layer by an ion beam stripping technology or an etching thinning technology.

In the embodiment of the present application, the thickness of the Fe-doped InP thin film layer may be 100nm-1 um.

S3, preparing a waveguide layer and an active layer in sequence on the foreign substrate by adopting a heteroepitaxial growth method;

in the embodiment of the application, the heteroepitaxial growth method comprises a molecular beam epitaxial growth method or a chemical vapor phase epitaxial growth method.

In the embodiment of the present application, the waveguide layer may be a single waveguide layer, a dual waveguide layer, or a quantum well hybrid waveguide layer, and the active layer includes a barrier layer.

S4, carrying out raster etching on the active layer and preparing an electrode contact layer on the active layer;

in the embodiment of the present application, as shown in fig. 2, specifically, the performing grating etching on the active layer includes etching away a part of the active layer, and then performing grating etching; the grating etching method may be a dry etching method, and optionally, the grating etching method may also be a wet etching method.

S5, etching the waveguide layer, the active layer and the electrode contact layer to prepare a distributed feedback laser and an amplifier, optionally, a distributed feedback laser and a modulator; the distributed feedback laser and the amplifier or modulator can share an active layer.

S6, preparing a waveguide contact layer and a detector structure on the Fe-doped InP thin film layer in sequence by adopting a selective area epitaxy method; the detector structure is a three-layer structure; the Fe-doped InP film is used as an insulating layer and has the functions of electrically isolating different devices and forming refractive index difference with the waveguide contact layer, so that light is better limited in the waveguide contact layer.

And S7, etching the detector structure to prepare the detector. The detector is located above the waveguide contact layer, which may be of the type of a PIN detector, and the detector receiving surface is located below.

Thus, the embodiment of the application can realize that the distributed feedback laser, the waveguide, the amplifier/modulator and the detector form the photonic integrated module on the SiC substrate.

In the embodiment of the application, the connection mode of the Fe-doped InP thin film layer and the single crystal SiC substrate layer is bonding connection. The bonding may be direct bonding, and optionally, the bonding may also be metal bonding.

In embodiments of the present application, the distributed feedback laser and the amplifier/modulator can share an active layer.

In the preparation method of the SiC-based InP photonic integrated module provided in the embodiment of the present application, InP is combined with a SiC-based substrate, and a low thermal resistance and high density SiC-based InP photonic integrated module is provided by using the properties that SiC has high thermal conductivity, has a certain refractive index difference with an InP thin film, and has a thermal expansion coefficient close to that of InP in a direction perpendicular to a C axis.

The present invention is not intended to be limited to the particular embodiments shown and described, but is to be accorded the widest scope consistent with the principles and novel features herein disclosed.

Claims

1. A preparation method of a SiC-based InP photonic integrated module is characterized by comprising the following steps:

obtaining a monocrystalline SiC substrate layer;

sequentially laminating and preparing a waveguide layer and an active layer on the heterogeneous substrate by adopting a heteroepitaxial growth method;

etching the waveguide layer, the active layer and the electrode contact layer to prepare a distributed feedback laser and any one of an amplifier and a modulator, wherein the distributed feedback laser and the amplifier or the modulator share the same active layer;

and etching the detector structure to prepare the detector.

2. The method for preparing the SiC-based InP photonic integrated module according to claim 1, wherein preparing the Fe-doped InP thin film layer on the single-crystal SiC substrate layer specifically comprises:

3. The method of fabricating an SiC-based InP photonic integrated module of claim 1, where the thickness of the Fe-doped InP thin film layer is 100nm-1 um.

4. The method of fabricating a SiC-based InP photonic integrated module as claimed in claim 1, wherein the heteroepitaxial growth method comprises a molecular beam epitaxy method or a chemical vapor phase epitaxy method.

5. The method of fabricating a SiC-based InP photonic integrated module of claim 1, wherein the waveguide layer comprises a single waveguide layer, a dual waveguide layer, or a quantum well hybrid waveguide layer.

6. The method of fabricating a SiC-based InP photonic integrated module as claimed in claim 1, wherein the active layer comprises a barrier layer.

7. The method for preparing the SiC-based InP photonic integrated module as claimed in claim 1, wherein the grating etching method comprises a dry etching method or a wet etching method.

8. A SiC-based InP photonic integrated module prepared by the preparation method of any one of claims 1 to 7, comprising: the device comprises a single crystal SiC substrate layer, an Fe-doped InP thin film layer, an amplifier/modulator, a distributed feedback laser and a detector;

the amplifier/modulator, the distributed feedback laser and the detector are integrated on the foreign substrate.

9. The SiC-based InP photonic integrated module of claim 8, where the Fe-doped InP thin film layer and the single-crystal SiC substrate layer are bonded.