CN113224187A

CN113224187A - Composite film and method for producing same

Info

Publication number: CN113224187A
Application number: CN202010071732.5A
Authority: CN
Inventors: 张秀全; 朱厚彬; 李真宇; 薛海蛟; 李洋洋; 张涛
Original assignee: Jinan Jingzheng Electronics Co Ltd
Current assignee: Jinan Jingzheng Electronics Co Ltd
Priority date: 2020-01-21
Filing date: 2020-01-21
Publication date: 2021-08-06

Abstract

Disclosed are a composite film and a method for preparing the same, the composite film may include: a substrate; a first isolation layer on a top surface of the substrate; an optical thin film structure is on the first isolation layer and includes a stacked structure formed of a light modulation layer, a light transmission layer, and an active layer generating light. The active layer may be in contact with one of the light modulation layer and the light transmission layer.

Description

Composite film and method for producing same

Technical Field

The present invention relates to a composite thin film and a method of manufacturing the same, and more particularly, to a composite thin film including an active layer, a light transmission layer, and a light modulation layer, and a method of manufacturing the same.

Background

A group III-V compound semiconductor such as indium phosphide or the like can have a direct bandgap structure and have a large bandgap (for example, a bandgap larger than 1.1 eV), and the wavelength of light emitted by a group III-V compound semiconductor such as indium phosphide or the like is suitable for optical fiber communication, and therefore, a group III-V compound semiconductor such as indium phosphide or the like is widely used in the field of optical communication as a light emitting material.

Electro-optical materials such as lithium niobate, lithium tantalate, etc. may have excellent nonlinear optical characteristics, electro-optical characteristics, and acousto-optical characteristics, which have wide applications in the fields of optical signal processing, information storage, etc. For example, the electro-optic effect of the electro-optic material can be used to modulate the phase, amplitude, intensity, or polarization state of light emitted by the light-emitting material, thereby loading information onto the light wave. Therefore, the electro-optical material can be widely applied to the fields of optical communication, high-power laser synthesis, laser radar, precision measurement, sensors and the like as an optical modulation layer or a waveguide layer. However, when the electro-optical material is used to form an optical waveguide structure, since it is difficult to etch, the surface of the electro-optical material is roughened by a conventional etching process, and thus optical loss is increased. Therefore, in order to reduce optical loss, special etching techniques are usually required to obtain a flat etched surface, which limits the application of the above-mentioned electro-optic materials.

Optical waveguide materials such as silicon, silicon nitride, silicon oxide, etc. have a large forbidden bandwidth and a high refractive index, and thus optical waveguide materials such as silicon, silicon nitride, silicon oxide, etc. can have a good light transmission performance. In addition, in the existing optical waveguide manufacturing process, optical waveguide materials such as silicon, silicon nitride, silicon oxide, and the like are easily processed, and the manufacturing process of the above optical waveguide materials is mature.

In the embodiment according to the present disclosure, by combining the above three materials, the light emitting characteristics of a group III-V compound semiconductor such as indium phosphide or the like, the electro-optical characteristics of a material such as lithium niobate, lithium tantalate or the like, and the light transmitting characteristics of an optical waveguide material such as silicon, silicon nitride, silicon oxide or the like can be simultaneously utilized, and thus a composite film having excellent performance can be prepared. The composite film can easily realize stable and effective industrial production and has very wide application prospect.

Disclosure of Invention

Technical problem

It is an object of the present disclosure to provide a composite thin film including a light modulation layer, a light transmission layer, and an active layer.

It is an object of the present disclosure to provide a method of manufacturing a composite film.

The present disclosure is directed to providing a composite film to solve the problem that an electro-optical crystal such as lithium niobate is difficult to process, and thus, industrial production of an electro-optical device including the same can be realized.

Technical scheme

A composite film according to an embodiment of the present disclosure may include: a substrate; a first isolation layer on a top surface of the substrate; an optical thin film structure is on the first isolation layer and includes a stacked structure formed of a light modulation layer, a light transmission layer, and an active layer generating light. The active layer may be in contact with one of the light modulation layer and the light transmission layer.

In an embodiment according to the present disclosure, in the optical thin film structure, the light modulation layer may be disposed on the first isolation layer, the light transmission layer may be disposed on the light modulation layer, and the active layer may be disposed on the light transmission layer.

In an embodiment according to the present disclosure, in the optical thin film structure, the active layer may be disposed on the first isolation layer, the light transmission layer may be disposed on the active layer, and the active light modulation layer may be disposed on the light transmission layer.

In an embodiment according to the present disclosure, the optical film structure may further include a second isolation layer between the light transmission layer and the light modulation layer.

In an embodiment according to the present disclosure, the composite film further includes a compensation layer on a bottom surface of the substrate opposite the top surface, the compensation layer may have the same material as the first isolation layer.

In an embodiment according to the present disclosure, the first isolation layer is a single layer structure or a multi-layer structure.

In an embodiment according to the present disclosure, when the first isolation layer is a multi-layer structure, the first isolation layer includes a stack structure formed by alternately stacking silicon oxide and silicon nitride.

In embodiments according to the present disclosure, the light modulation layer may include lithium niobate, lithium tantalate, KDP, DKDP, or quartz.

In embodiments according to the present disclosure, the light wave transmitting layer comprises silicon or silicon nitride.

In an embodiment according to the present disclosure, the active layer is formed of at least one of GaN, GaAs, GaSb, InP, AlAs, AlGaAs, AlGaAsP, GaAsP, and InGaAsP when viewed in a cross-sectional view.

A method of making a composite film according to embodiments of the present disclosure may include: depositing a first isolation layer on an upper surface of a first substrate; and forming an optical thin film layer on the first isolation layer. The optical thin film layer may include a stacked structure formed of a light modulation layer, a light transmission layer, and an active layer generating light, the active layer being in contact with one of the light modulation layer and the light transmission layer.

In an embodiment according to the present disclosure, the step of forming the optical thin film layer on the first isolation layer may include: the light modulation layer, the light transmission layer and the active layer of the optical thin film layer are formed by an ion implantation process and a wafer bonding process, respectively.

In an embodiment according to the present disclosure, the optical thin film layer further includes a second isolation layer between the light modulation layer and the light transmission layer, the second isolation layer being formed by performing a thermal oxidation process on the substrate for forming the light transmission layer.

In an embodiment according to the present disclosure, the step of forming the optical thin film layer on the first isolation layer may include: forming a light modulation layer on the first isolation layer; forming a light transmission layer on the light modulation layer; and forming an active layer on the light transmission layer. The step of forming the light modulation layer may include: implanting ions into one surface of the electro-optic material substrate by using an ion implantation method so as to form a thin film layer and a residual material layer and an implantation layer positioned between the thin film layer and the residual material layer in the electro-optic material substrate, wherein the implanted ions are distributed in the implantation layer; contacting the surface of the electro-optical material substrate on which the thin film layer is formed with the upper surface of the first isolation layer to form a first bonding body; heating the first bonding body to a preset temperature and preserving heat for a preset time so as to transfer the thin film layer to the first isolation layer; and grinding and polishing the thin film layer to a predetermined thickness, thereby obtaining a first composite structure including the substrate, the first spacer layer, and the light modulation layer. The step of forming the light transmission layer may include: implanting ions into one surface of the optical transmission material substrate by an ion implantation method to form a thin film layer and a surplus material layer and an implanted layer between the thin film layer and the surplus material layer in the optical transmission material substrate, the implanted ions being distributed in the implanted layer; contacting the surface of the light transmission material substrate on which the thin film layer is formed with the upper surface of the light modulation layer to form a second bonding body; heating the second bonding body to a predetermined temperature and holding the temperature for a predetermined time to transfer the thin film layer onto the light modulation layer; and grinding and polishing the thin film layer to a predetermined thickness to obtain a second composite structure including the substrate, the first isolation layer, the light modulation layer, and the light transmission layer. The forming of the active layer may include: implanting ions into one surface of the active material substrate by using an ion implantation method, thereby forming a thin film layer and a residue layer and an implanted layer located between the thin film layer and the residue layer in the active material substrate, wherein the implanted ions are distributed in the implanted layer; contacting the surface of the active material substrate on which the thin film layer is formed with the upper surface of the light transmission layer to form a third bonding body; heating the third bonded body to a predetermined temperature and holding it for a predetermined time to transfer the thin film layer to the light transmission layer; and grinding and polishing the thin film layer to a predetermined thickness, thereby obtaining a composite thin film including the substrate, the first isolation layer, the light modulation layer, the light transmission layer, and the active layer.

In an embodiment according to the present disclosure, the step of forming the optical thin film layer on the first isolation layer may include: the light modulation layer and the active layer are formed using an ion implantation process and a wafer bonding process, respectively, and the light transmission layer is formed using a deposition process.

In an embodiment according to the present disclosure, the light transmission layer is formed by LPCVD.

In an embodiment according to the present disclosure, the step of forming the optical thin film layer on the first isolation layer may include: forming a light modulation layer on the first isolation layer; forming a light transmission layer on the light modulation layer by using a deposition process; and forming an active layer on the light transmission layer. The step of forming the light modulation layer may include: implanting ions into one surface of the electro-optic material substrate by using an ion implantation method so as to form a thin film layer and a residual material layer and an implantation layer positioned between the thin film layer and the residual material layer in the electro-optic material substrate, wherein the implanted ions are distributed in the implantation layer; contacting the surface of the electro-optical material substrate on which the thin film layer is formed with the upper surface of the first isolation layer to form a first bonding body; heating the first bonding body to a preset temperature and preserving heat for a preset time so as to transfer the thin film layer to the first isolation layer; and grinding and polishing the thin film layer to a predetermined thickness, thereby obtaining a first composite structure including the substrate, the first spacer layer, and the light modulation layer. The forming of the active layer may include: implanting ions into one surface of the active material substrate by using an ion implantation method, thereby forming a thin film layer and a residue layer and an implanted layer located between the thin film layer and the residue layer in the active material substrate, wherein the implanted ions are distributed in the implanted layer; contacting the surface of the active material substrate on which the thin film layer is formed with the upper surface of the light transmission layer to form a fourth bonding body; heating the fourth bonded body to a predetermined temperature and holding it for a predetermined time to transfer the thin film layer to the light transmission layer; and grinding and polishing the thin film layer to a predetermined thickness, thereby obtaining a composite thin film including the substrate, the first isolation layer, the light modulation layer, the light transmission layer, and the active layer.

In an embodiment according to the present disclosure, the step of forming the optical thin film layer on the first isolation layer may include: forming a light modulation layer on the first isolation layer; depositing a sacrificial isolation layer on an upper surface of a second substrate; forming an active layer on the sacrificial isolation layer; depositing a light transmission layer on the active layer using a deposition process; contacting the light transmitting layer with the light modulation layer to form a sixth bonding body; heating the sixth bonding body to a preset temperature and preserving heat for a preset time; and removing the second substrate and the sacrificial isolation layer through an etching process to obtain the composite thin film. The step of forming the light modulation layer may include: implanting ions into one surface of the electro-optic material substrate by using an ion implantation method so as to form a thin film layer and a residual material layer and an implantation layer positioned between the thin film layer and the residual material layer in the electro-optic material substrate, wherein the implanted ions are distributed in the implantation layer; contacting the surface of the electro-optical material substrate on which the thin film layer is formed with the upper surface of the first isolation layer to form a first bonding body; heating the first bonding body to a preset temperature and preserving heat for a preset time so as to transfer the thin film layer to the first isolation layer; and grinding and polishing the thin film layer to a predetermined thickness, thereby obtaining a first composite structure including the substrate, the first spacer layer, and the light modulation layer. The forming of the active layer may include: implanting ions into one surface of the active material substrate by using an ion implantation method, thereby forming a thin film layer and a residue layer and an implanted layer located between the thin film layer and the residue layer in the active material substrate, wherein the implanted ions are distributed in the implanted layer; contacting the surface of the active material substrate, on which the thin film layer is formed, with the upper surface of the sacrificial isolation layer to form a fifth bonding body; heating the fifth bonding body to a preset temperature and preserving heat for a preset time so as to transfer the thin film layer to the sacrificial isolating layer; and grinding and polishing the thin film layer to a predetermined thickness to obtain a third composite thin film including the second substrate, the sacrificial isolation layer and the active layer.

Advantageous effects

In an embodiment according to the present disclosure, a composite thin film including an active layer, a light transmission layer, and a light modulation layer may be obtained by the above-described method. In the embodiment according to the present disclosure, since the light transmission layer formed of a conventional optical waveguide material and the light modulation layer formed of an electro-optical crystal such as lithium niobate are combined to form a composite film applied to an electro-optical device, a complicated process for processing lithium niobate can be avoided, and thus industrial production of an electro-optical device including an electro-optical crystal such as lithium niobate can be realized. In an embodiment according to the present disclosure, the first isolation layer may be a stacked structure in which layers having different refractive indices from each other are alternately stacked, so that a quantum well may be formed between the optical thin film structure and the substrate to reflect light leaked from the optical thin film structure back to the optical thin film structure, thereby reducing optical loss. In an embodiment according to the present disclosure, substrate warpage is improved by forming a compensation layer on a bottom surface of a substrate such that stresses applied to both faces of the substrate cancel each other out.

Drawings

These and/or other aspects will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a cross-sectional view of a composite film according to an exemplary embodiment of the present disclosure;

FIG. 2 is a cross-sectional view of an optoelectronic film according to another exemplary embodiment of the present disclosure; and

fig. 3 to 15 are cross-sectional views of a method of manufacturing a composite film according to an exemplary embodiment of the present disclosure.

Reference numerals:

100. 200-composite film 110-first substrate

130-first spacer 150-light modulating layer

170-optical transport layer 190-active layer

160-second isolation layer 130' -Compensation layer

150-1-electro-optic material substrate 170-1-optical transmission material substrate

190-1-active material substrate 150-11, 170-11, 190-11-thin film layer

150-12, 170-12, 190-12-separation layer 150-13, 170-13, 190-13-residue layer

210-second substrate 230-sacrificial isolation layer

A. B-optical film structure

Detailed Description

The principles of the present invention will be described in further detail below with reference to the accompanying drawings and exemplary embodiments so that the technical solutions of the present invention will be clear. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the embodiments of the invention to those skilled in the art. While example embodiments may be practiced differently, the specific process sequence may be performed in an order different than that described. For example, two consecutively described processes may be performed substantially simultaneously or in reverse order to that described. In addition, like reference numerals in the drawings denote like elements. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity.

When an element or layer is referred to as being "on," "connected to," or "coupled to" another element or layer, it can be directly on (or directly on, or directly coupled to) the other element or layer, or intervening elements or layers may be present. However, when an element or layer is referred to as being "directly on," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present.

Fig. 1 is a cross-sectional view of a composite film according to an exemplary embodiment of the present disclosure. Hereinafter, a composite film 100 according to an exemplary embodiment of the present disclosure will be described in detail with reference to fig. 1.

Referring to fig. 1, a composite film 100 according to an exemplary embodiment of the present invention may include a first substrate 110, a first isolation layer 130, and an optical film structure a. The optical film structure a may include a light modulation layer (or electro-optic material layer) 150, a light transmission layer 170, and an active layer 190.

Specifically, as shown in fig. 1, the first isolation layer 130 may be disposed on the first substrate 110 and cover an upper surface of the first substrate 110. The optical thin film structure a may be disposed on the first isolation layer 130 and separated from the first substrate 110 by the first isolation layer 130, and thus light leakage from the optical thin film structure a to the first substrate 110 may be prevented.

In the optical thin film structure a, a light modulation layer 150, a light transmission layer 170, and an active layer 190 may be sequentially stacked. Specifically, the light modulation layer 150 may be disposed on the first isolation layer 130 and separated from the first substrate 110 by the first isolation layer 130, the light transmission layer 170 may be disposed on the light modulation layer 150 and cover a top surface of the light modulation layer 150, and the active layer 190 may be disposed on a top surface of the light transmission layer 170. However, in an embodiment according to the present disclosure, the stacking order of the light modulation layer 150, the light transmission layer 170, and the active layer 190 is not limited thereto, and for example, the active layer 190 may be in contact with one of the light modulation layer 150 and the light transmission layer 170.

The layers of the composite film 100 will be described in detail below with reference to fig. 1.

The first substrate 110 may be used to support a film or a component thereon. According to an exemplary embodiment of the present disclosure, the first substrate 110 may be a silicon substrate, a quartz substrate, a silicon oxide substrate, lithium niobate (LN, LiNiO)₃) Substrate or lithium tantalate (LT, LiTaO)₃) A substrate, etc. However, according to example embodiments of the present disclosure, not limited thereto, the first substrate 110 may be formed of other suitable materials. In the embodiment according to the present disclosure, for convenience of description, a case where the first substrate 110 is a silicon substrate will be described as an example. In addition, the first substrate 110 may have a thickness from the order of micrometers to the order of millimeters. For example, the thickness of the first substrate 110 may be about 0.1mm to about 1 mm. Preferably, the thickness of the first substrate 110 may be about 0.1mm to about 0.2mm, about 0.3mm to about 0.5mm, or about 0.2mm to about 0.5 mm.

The first separation layer 130 may be positioned between the first substrate 110 and the optical thin film structure a to separate the substrate 110 from the optical thin film structure a. The first separation layer 130 may have a refractive index smaller than that of a layer in the optical thin film structure a in contact with the first separation layer 130, and thus light transmitted in the optical thin film structure a may be prevented from leaking.

The first isolation layer 130 may be a single layerA layer or a plurality of layers. In exemplary embodiments according to the present disclosure, the first isolation layer 130 may be made of silicon oxide (SiO)_x) And silicon nitride (SiN)_y) Is made of, for example, SiO, the first isolation layer 130 may be made of₂Formed as a single layer or from SiO₂And Si₃N₄The formed layers are alternately stacked. However, exemplary embodiments according to the present disclosure are not limited thereto, and the first isolation layer 130 may be made of any suitable material. When the first isolation layer 130 is made of silicon oxide (SiO)_x) And silicon nitride (SiN)_y) When the plurality of layers are alternately stacked, since the material layers alternately stacked in the first separation layer 130 have a refractive index difference, a quantum well may be formed between the optical thin film structure a and the first substrate 110, and thus light leakage may be further prevented and light loss may be reduced.

In addition, in an exemplary embodiment according to the present disclosure, the first isolation layer 130 may have a distance of about 10nm to about 10 μm when viewed in a cross-sectional view. Preferably, the thickness of the first isolation layer 130 may be about 100nm to about 8 μm, about 500nm to about 6 μm, or about 1 μm to about 4 μm, or any range defined by these numbers.

The light modulation layer 150 may be disposed on the first isolation layer 130. The light modulation layer 150 may cover a top surface of the first isolation layer 130 when viewed in a plan view. The light modulation layer 150 may be used to modulate an optical signal based on the electro-optic effect. In an embodiment according to the present disclosure, the light modulation layer 150 may include lithium niobate, lithium tantalate, KDP (potassium dihydrogen phosphate), DKDP (potassium dideuterium phosphate), quartz, or the like. However, embodiments according to the present disclosure are not limited thereto. In the embodiment according to the present disclosure, for convenience of description, a case where the light modulation layer 150 includes lithium niobate will be described as an example.

In addition, the light modulation layer 150 may have a thickness of about 100nm to about 100 μm. Preferably, the thickness of the light modulation layer 190 may be about 200nm to about 80 μm, about 300nm to about 60 μm, about 400nm to about 40 μm, about 500nm to about 20 μm, about 600nm to about 1 μm, or any range defined by these numbers, for example, about 500nm to about 60 μm or about 300nm to about 40 μm, and the like.

The light transmission layer 170 may be an optical waveguide layer for transmitting light. As shown in fig. 1, the light transmission layer 170 may be disposed on the light modulation layer 150. In exemplary embodiments according to the present disclosure, the light transmission layer 170 may be formed of silicon, silicon nitride, silicon oxide, or the like. However, exemplary embodiments according to the present disclosure are not limited thereto, and for example, the light transmission layer 170 may be formed of any suitable material. In the embodiment according to the present disclosure, for convenience of description, a case where the light transmission layer 170 is formed of silicon or silicon nitride will be described as an example.

The thickness of the light transmission layer 170 may affect the quality and capacity of the transmitted light. When the thickness of the light transmission layer 170 is thin, the transmitted light may be single-mode light, and the transmission quality of the light is good. When the thickness of the light transmission layer 170 becomes larger, the mode of the transmitted light may increase, thereby increasing the transmission capacity, but as the thickness of the light transmission layer 170 increases, the mode of the transmitted light increases, thereby causing a mixing condition, thereby decreasing the quality of the light transmission. In embodiments according to the present disclosure, the thickness of the light transmission layer 170 may be about 50nm to about 2 μm. Preferably, the thickness of the light transmission layer 170 may be about 50nm to about 1.8 μm, about 50nm to about 1.6 μm, about 200nm to about 1.4 μm, about 400nm to about 1.2 μm, about 600nm to about 1 μm, or any range defined by these numbers, for example, about 400nm to about 1.8 μm or about 200nm to about 1.6 μm, and so forth.

The active layer 190 may be used to generate predetermined light. As shown in fig. 1, the active layer 190 may be disposed on the light transmission layer 170. In exemplary embodiments according to the present disclosure, the active layer 190 may be formed of a III-V compound semiconductor. Specifically, the active layer 160 may be formed of at least one of GaN, GaAs, GaSb, InP, AlAs, AlGaAs, AlGaAsP, GaAsP, and InGaAsP. However, exemplary embodiments according to the present disclosure are not limited thereto. In the embodiment according to the present disclosure, for convenience of description, a case where the active layer 190 is formed of InP will be described as an example.

In an embodiment according to the present disclosure, the thickness of the active layer 190 may be about 50nm to about 2 μm. Preferably, the thickness of the active layer 190 may be about 100nm to about 1.5 μm, about 200nm to about 1 μm, about 200nm to about 900nm, about 300nm to about 700nm, about 300nm to about 500nm, or any range defined by these numbers, for example, about 100nm to about 900 μm or about 200nm to about 700 μm, and the like.

Although a structure in which the light modulation layer 150, the light transmission layer 170, and the active layer 190 are sequentially stacked is illustrated in fig. 1, the stacking order of the light modulation layer 150, the light transmission layer 170, and the active layer 190 is not limited thereto in the embodiment according to the present disclosure. For example, in one embodiment, the active layer 190 may be disposed directly on the first isolation layer 130, and the light modulation layer 150 may be disposed between the active layer 190 and the light transmission layer 170. In another embodiment, the active layer 190 may be disposed directly on the first isolation layer 130, and the light transmission layer 170 may be located between the active layer 190 and the light modulation layer 150.

In addition, the composite film 100 or the optical film structure a according to the present disclosure is not limited to the above-described structure. For example, the composite film 100 or optical film structure A may also include other functional layers.

Fig. 2 is a cross-sectional view illustrating an optoelectronic film according to another exemplary embodiment of the present disclosure. The differences between the composite film 200 or the optical film structure B shown in fig. 2 and the composite film 100 or the optical film structure a shown in fig. 1 will be mainly described below. Herein, like reference numerals denote like elements, and a repetitive description of the same elements will be omitted in order to avoid redundancy.

As shown in fig. 2, the composite film 200 may further include a compensation layer 130' disposed on the bottom surface of the first substrate 110. The compensation layer 130 'may have the same structure as the first isolation layer 130, or the compensation layer 130' and the first isolation layer 130 may have a symmetrical structure with respect to the first substrate 110. In particular, the compensation layer 130' may be made of silicon oxide (SiO)_x) And silicon nitride (SiN)_y) Is made of at least one of, for example, SiO, the compensation layer 130' may be made of₂Formed as a single layer orFrom SiO₂And Si₃N₄The formed layers are alternately stacked. In addition, the compensation layer 130' and the first isolation layer 130 may be simultaneously formed through the same process. In the embodiment according to the present invention, the compensation layer 130' may suppress the first substrate 110 from being warped when the first isolation layer 130 is formed.

As shown in fig. 2, the optical thin film structure B may further include a second isolation layer 160 disposed between the light modulation layer 150 and the light transmission layer 170, as compared to the optical thin film structure a in fig. 1. The second isolation layer 160 may be made of silicon oxide (SiO)_x) The second isolation layer 160 may be formed of, for example, SiO₂A single layer is formed.

The second isolation layer 160 may have a refractive index lower than those of the light transmission layer 170 and the light modulation layer 150. Therefore, the second isolation layer 160 may prevent light from leaking from the light transmission layer 170 into the light modulation layer 150, and may reduce the transmission loss of light. In this case, the light modulation layer 150 and the light transmission layer 170 may be separated such that the transmission of light and the modulation of light are independent of each other.

In an embodiment according to the present disclosure, the thickness of the second isolation layer 160 may be about 10nm to about 100 nm. Preferably, the thickness of the second isolation layer 160 may be about 10nm to about 90nm, about 10nm to about 80nm, about 20nm to about 70nm, about 30nm to about 60nm, about 40nm to about 50nm, or any range defined by these numbers, for example, about 10nm to about 60nm, etc.

Fig. 3 to 15 are cross-sectional views of a method of manufacturing a composite film according to an exemplary embodiment of the present disclosure. A method of manufacturing a composite film according to an exemplary embodiment of the present invention will be described in detail below with reference to fig. 3 to 15.

As shown in fig. 3, first, a first substrate 110 is prepared, and then a first isolation layer 130 may be formed on an upper surface of the first substrate 110 by, for example, a Plasma Enhanced Chemical Vapor Deposition (PECVD) process, a Low Pressure Chemical Vapor Deposition (LPCVD), or a thermal oxidation method.

For example, when the first isolation layer 130 includes a plurality of layers, silicon oxide and silicon nitride may be alternately deposited on the upper surface of the first substrate 110 through a deposition process to form the first isolation layer 130 having a quantum well structure. In another embodiment according to the present disclosure, when the first isolation layer 130 includes a single layer, silicon oxide may be formed on the first substrate 110 by a thermal oxidation method.

In addition, when the composite film includes the compensation layer 130', the compensation layer 130' may be formed on the bottom surface of the first substrate 110 at the same time as the first isolation layer 130 is formed, and the first isolation layer 130 and the compensation layer 130' may have a structure symmetrical to each other.

Next, a process of forming an optical thin film structure on the first isolation layer 130 will be described. Since the light modulation layer, the light transmission layer, and the active layer in the optical thin film structure have different stacking orders, the order of forming the light modulation layer, the light transmission layer, and the active layer may be changed according to the stacking order of the light modulation layer, the light transmission layer, and the active layer in the optical thin film structure.

A method of forming the light modulation layer, the light transmission layer, and the active layer in the optical thin film structure a on the first isolation layer 130 by ion implantation and a wafer bonding process, respectively, will be described below with reference to fig. 4 to 11.

Fig. 4 to 6 illustrate a process of forming the light modulation layer 150.

As shown in fig. 4, an electro-optic material substrate 150-1 is prepared, and then, the electro-optic material substrate 150-1 is ion-implanted by an ion implantation method, so that the electro-optic material substrate 150-1 is formed to include a thin film layer 150-11, a residue layer 150-13, and a separation layer 150-12 between the thin film layer 150-11 and the residue layer 150-13, and implanted ions are distributed in the separation layer 150-12.

During the ion implantation process, ions (e.g., H) may be utilized⁺、H₂ ⁺、He⁺Or He²⁺) Ion implantation is performed on one surface of the electro-optic material substrate 150-1 to form a separation layer (may also be referred to as an implantation layer) 150-12 in the electro-optic material substrate 150-1. Implanted ions may be distributed within the separation layer 150-12. The separation layer 150-12 may divide the electro-optic material substrate 150-1 into an upper region and a lower region: a region through which most of the implanted ions passReferred to as thin film layers 150-11; the other is the region where most of the implanted ions do not pass, referred to as the residual layer 150-13. The thickness of the thin film layer 150-11 is determined by the energy of ion implantation, etc. For example, in an exemplary embodiment according to the present invention, the ion implantation energy may be about 100 to 800KeV, about 150 to 750KeV, about 170 to 700KeV, about 180 to 650KeV, about 190 to 600KeV, about 200 to 550KeV, about 210 to 500KeV, about 220 to 450KeV, about 230 to 400KeV, about 240 to 350KeV, about 250 to 300KeV, or any range defined by these numbers, such as about 160 to 400KeV, about 180 to 600KeV, or about 200 to 750KeV, etc. In an exemplary embodiment according to the present invention, the ion implantation dose may be about 1 × 10¹⁵～1×10¹⁷ions/cm²About 1X 10¹⁵～6×10¹⁶ions/cm²About 1X 10¹⁵～4×10¹⁶ions/cm²About 2X 10¹⁵～1×10¹⁷ions/cm²About 4X 10¹⁵～1×10¹⁷ions/cm²Or within any range defined by these numbers, e.g., about 2X 10¹⁵～6×10¹⁶ions/cm²Or about 2X 10¹⁵～4×10¹⁶ions/cm²And so on.

In addition, the ion implantation method may include a conventional ion implanter implantation method, a plasma immersion ion implantation method, and an ion implantation method using a segmented implantation of different implantation temperatures.

Here, the ion implantation is performed in order to implant a large amount of ions into the surface layer of the electro-optical material substrate 150-1, the implanted ions in the separation layer 150-12 are in an unstable state within the electro-optical material substrate 150-1, the implanted ions are embedded in lattice defects, volume strain is generated, and the separation layer becomes a stress concentration region, so that the mechanical strength of a portion of the electro-optical material substrate 150-1 in the vicinity of the separation layer 150-12 is reduced.

Next, as shown in fig. 5, the thin film layer 150-11 of the electro-optical material substrate 150-1 and the polished surface of the first spacer 130 are brought close to each other by a wafer bonding method, and then bonded together, and pressure is applied thereto to form a first bond shown in fig. 5. Due to the action of the molecular forces (e.g., van der waals forces) of the surfaces of the thin film layer 150-11 and the first separation layer 130, the molecules of the two surfaces are in direct contact, thereby forming a bond. However, example embodiments of the present invention are not limited thereto. For example, the bonding body may be formed only by intermolecular force without applying pressure to the two substrates. According to the present invention, the wafer bonding method may be selected from any one of a direct bonding method, an anodic bonding method, a low temperature bonding method, a vacuum bonding method, a plasma enhanced bonding method, and an adhesive bonding method.

Next, as shown in fig. 6, the first bond is put into a heating apparatus to be kept at a predetermined temperature for a predetermined time. In this process, the ions in the separation layer 150-12 chemically react to become gas molecules or atoms and generate tiny bubbles, and as the heating time is prolonged or the heating temperature is increased, the bubbles increase more and the volume of the bubbles increases gradually. When these bubbles are united into one piece, the separation of the residual material layer 150-13 from the separation layer 150-12 is achieved, so that the thin film layer 150-11 is transferred to the first separation layer 130 and forms a first initial composite structure. The first initial composite structure may then be placed in a heating apparatus to be held at a predetermined temperature for a predetermined time to eliminate damage caused by the ion implantation process. Then, the thin film layer 150-11 on the first spacer 130 may be ground and polished to a predetermined thickness to form the light modulation layer 150 on the first spacer 130, and a first composite structure is obtained.

Fig. 7 to 9 illustrate a process of forming the light transmission layer 170.

As shown in fig. 7 and 9, similarly to the process described with reference to fig. 4 to 6, the light transmission material substrate 170-1 is prepared, and then, the light transmission material substrate 170-1 is ion-implanted by an ion implantation method, so that the light transmission material substrate 170-1 is formed to include the thin film layer 170-11, the surplus layer 170-13, and the separation layer 170-12 between the thin film layer 170-11 and the surplus layer 170-13.

Next, the thin film layer 170-11 of the light transmitting material substrate 170-1 and the polished surface of the light modulation layer 150 of the first composite structure are brought close to each other by a wafer bonding method, and then bonded together, and pressure is applied thereto to form a second bond shown in fig. 8.

Next, the second bond is placed in a heating apparatus to be kept at a predetermined temperature for a predetermined time to transfer the thin film layer 170-11 onto the light modulation layer 150, and a second initial composite structure is formed. The second initial composite structure may then be placed in a heating apparatus to be held at a predetermined temperature for a predetermined time to eliminate damage caused by the ion implantation process. Then, the thin film layer 170-11 on the light modulation layer 150 may be ground and polished to a predetermined thickness to form the light transmission layer 170 on the light modulation layer 150, and a second composite structure is obtained.

Further, as shown in fig. 2, when the optical thin film structure B includes the second isolation layer 160 between the light transmission layer 170 and the light modulation layer 150, a silicon oxide layer may be deposited on the light modulation layer 150 before the light transmission layer 170 is formed, and then the silicon oxide layer may be polished to a predetermined thickness to form the second isolation layer 160.

However, the process of forming the light transmission layer 170 is not limited to the processes described in fig. 7 to 9. For example, the light transmission layer may be formed using a deposition process. In one embodiment, when the light transmission layer 170 is formed of silicon nitride, a silicon nitride layer may be deposited on the light modulation layer 150 or the active layer 190 through a deposition process, and then a composite thin film is formed through a bonding process, which will be described later by way of specific embodiments.

Fig. 10 and 11 illustrate a process of forming the active layer 190.

As shown in fig. 10 and 11, similar to the process described with reference to fig. 4 to 6, an active material substrate 190-1 is prepared, and then, the active material substrate 190-1 is ion-implanted by an ion implantation method, so that the active material substrate 190-1 is formed to include a thin film layer 190-11, a residue layer 190-13, and a separation layer 190-12 between the thin film layer 190-11 and the residue layer 190-13.

Next, the thin film layer 190-11 of the light transmitting material substrate 190-1 and the polished surface of the light transmitting layer 170 are brought close to each other by a wafer bonding method, and then bonded together, and pressure is applied thereto to form a third bonded body shown in fig. 11.

The third bond is then placed in a heating apparatus to soak at a predetermined temperature for a predetermined time to allow transfer of film layer 190-11 to light transmitting layer 170 and form a third initial composite structure. The third initial composite structure may then be placed in a heating apparatus to soak at a predetermined temperature for a predetermined time to eliminate damage caused by the ion implantation process. Then, the thin film layer 190-11 on the light transmission layer 170 may be ground and polished to a predetermined thickness to form the active layer 190 on the light transmission layer 170, and a third composite structure is obtained.

In addition, the method of forming the composite thin film according to the embodiment of the present disclosure is not limited thereto. A method of manufacturing a composite film according to another embodiment of the present disclosure will be described below with reference to fig. 12 to 15, in which the steps of forming the first spacer layer 130 and the light modulation layer 150 are the same as those described with reference to fig. 3 to 6, and a description thereof will be omitted here.

As shown in fig. 12 and 13, a second substrate 210 is prepared, and a sacrificial isolation layer 230 is formed on the second substrate 210. Then, similarly to the step shown in fig. 10, ion implantation is performed on the active material substrate 190-1. Then, the thin film layer 190-11 of the light transmitting material substrate 190-1 and the polished surface of the sacrificial spacer layer 230 are brought close to each other by a wafer bonding method, and then bonded together, and pressure is applied thereto to form a fourth bonded body shown in fig. 12. Next, the fourth bonded assembly is placed in a heating apparatus to be held at a predetermined temperature for a predetermined time to allow the thin film layers 190-11 to transfer to the sacrificial barrier layer 230 and form a fourth initial composite structure. The fourth initial composite structure may then be placed in a heating apparatus to be held at a predetermined temperature for a predetermined time to eliminate damage caused by the ion implantation process. Then, the thin film layer 190-11 on the sacrificial isolation layer 230 may be ground and polished to a predetermined thickness to form the active layer 190 on the sacrificial isolation layer 230, and a fourth composite structure is obtained.

Next, as shown in fig. 14, a light transmission layer 170 is formed on the active layer 190 shown in fig. 13 through a deposition process. However, embodiments according to the present disclosure are not limited thereto, and for example, in another embodiment, the light transmission layer 170 may be formed on the light modulation layer 150 through a deposition process.

Next, as shown in fig. 15, the light transmission layer 170 and the light modulation layer 150 are brought close to each other by a wafer bonding method, and then bonded together, and pressure is applied thereto to form a fifth composite structure shown in fig. 15. Then, the second substrate 210 and the sacrificial spacer 230 are removed by dry etching to form a composite thin film.

The specific process of manufacturing the composite film according to the disclosed embodiments will be described in detail with reference to the embodiments.

Example 1

A silicon wafer substrate having a size of 3 inches and a thickness of 0.4mm was prepared, and had a smooth surface. After the silicon wafer substrate is thoroughly cleaned, SiO with the thickness of 2 mu m is formed on the smooth surface of the silicon wafer substrate by adopting a thermal oxidation method₂And (3) a layer.

Next, a lithium niobate wafer having a size of 3 inches was prepared as an electro-optical material substrate. The implantation dosage of the lithium niobate wafer is 4 multiplied by 10 by adopting an ion implantation method¹⁶ions/cm²Helium ion (He)¹⁺) And the implantation energy is 200 keV. And implanting ions into the lithium niobate wafer to form a thin film layer, a separation layer and a residual material layer. The thin film layer of the lithium niobate wafer and the SiO of the silicon wafer substrate are bonded by a plasma bonding method₂The layers are bonded to form a first bond. Then placing the first bonding body into heating equipment, and carrying out heat preservation for 4 hours at 350 ℃ until the thin film layer is transferred to SiO₂On the layer to obtain a first initial composite structure. And polishing the thin film layer to 400nm by using a Chemical Mechanical Polishing (CMP) method to obtain the first composite structure of the lithium niobate single crystal thin film with the nano-scale thickness.

Next, a silicon wafer having a size of 3 inches was prepared as a light transmission material substrate. The method adopts ion implantation to implant 6 × 10 dose into silicon wafer¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 40 keV. After ions are implanted into a silicon wafer, a thin film layer, a separation layer, and a residual material layer are formed.And bonding the thin film layer of the silicon wafer and the lithium niobate single crystal thin film by a plasma bonding method to form a second bonded body. And then placing the second bonding body into heating equipment, and preserving heat for 4h at 400 ℃ until the thin film layer of the silicon wafer is transferred to the lithium niobate single crystal thin film to obtain a second initial composite structure. The second initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. And finally, polishing the silicon single crystal film to 220nm to obtain a second composite structure with the double-layer nano-scale thickness film.

Next, an indium phosphide wafer having a size of 3 inches was prepared as a raw material substrate. The method of ion implantation is adopted to implant the dose of the InP wafer to be 6 multiplied by 10¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. After ions are implanted into the InP wafer, a thin film layer, a separation layer and a residual material layer are formed. And bonding the thin film layer of the indium phosphide wafer and the thin film layer of the silicon wafer by a plasma bonding method to form a third bonded body. And then putting the third bonding body into heating equipment, and carrying out heat preservation for 4 hours at 400 ℃ until the thin film layer of the indium phosphide wafer is transferred onto the thin film layer of the silicon wafer to obtain a third initial composite structure. The third initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. And finally, polishing the film layer of the indium phosphide wafer to 600nm to obtain the composite film with three layers of nano-scale thickness films.

In the composite film including the active layer, the light transmission layer and the light modulation layer obtained by the above method, light emitted from indium phosphide as a self-light emitting material can be transmitted to the silicon thin film layer, silicon can be easily processed into a waveguide and can transmit light, and when the size of the silicon waveguide layer is made sufficiently small, light can be easily transmitted to the lithium niobate layer and can be confined in the lithium niobate thin film layer for lateral propagation.

Example 2

A silicon wafer substrate having a size of 3 inches and a thickness of 0.4mm was prepared, and had a smooth surface. After the silicon wafer substrate is thoroughly cleaned, the method adoptsThermal oxidation method for forming SiO 2 μm thick on the smooth surface of silicon wafer substrate₂And (3) a layer.

Then, after cleaning the first composite structure, Si with the thickness of 700nm is formed on the lithium niobate single crystal film by adopting a PECVD mode₃N₄And (c) film to obtain a second initial composite structure. Then, Si will be reacted₃N₄The film was polished to 200nm to obtain a second composite structure.

Next, an indium phosphide wafer having a size of 3 inches was prepared as a raw material substrate. The method of ion implantation is adopted to implant the dose of the InP wafer to be 6 multiplied by 10¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. After ions are implanted into the InP wafer, a thin film layer, a separation layer and a residual material layer are formed. Bonding the thin film layer of the InP wafer with the Si by plasma bonding₃N₄And bonding the film to form a second bonded body. Then placing the second bonding body into heating equipment, and carrying out heat preservation for 4h at 400 ℃ until the thin film layer of the indium phosphide wafer is transferred to the Si₃N₄On the film to obtain a third initial composite structure. The third initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. Finally, polishing the thin film layer of the indium phosphide wafer to 600nm,obtaining the composite film with three layers of nano-scale thickness films.

In the composite film including the active layer, the light transmission layer and the light modulation layer obtained by the above method, light emitted from indium phosphide as a self-light emitting material can be transmitted to the silicon nitride layer, the silicon nitride layer is easy to process into a waveguide and can transmit light, and when the size of the silicon nitride waveguide layer is made sufficiently small, light can be easily transmitted to the lithium niobate layer and can be confined to propagate laterally within the lithium niobate thin film layer.

A composite thin film including an active layer, a light transmission layer, and a light modulation layer can be obtained by the above method. Compared with the composite film obtained in example 1, the refractive index of the silicon nitride layer is close to that of the lithium niobate layer, the coupling loss is low, the nonlinear absorption effect is avoided, and the optical transmission loss can be further reduced.

Example 3

Then, after cleaning the lithium niobate single crystal thin film layer, using PECVD at the temperature of 200-300 DEG CSiO 2.5 μm thick deposited on the crystalline thin film layer₂Then SiO₂The layers were ground and polished to 2 μm to form an isolation layer.

Next, a silicon wafer having a size of 3 inches was prepared as a light transmission material substrate. The method adopts ion implantation to implant 6 × 10 dose into silicon wafer¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 40 keV. After ions are implanted into a silicon wafer, a thin film layer, a separation layer, and a residual material layer are formed. And bonding the thin film layer of the silicon wafer and the silicon dioxide layer by a plasma bonding method to form a second bonded body. And then placing the second bonding body into heating equipment, and carrying out heat preservation for 4h at 400 ℃ until the thin film layer of the silicon wafer is transferred to the silicon dioxide layer to obtain a second initial composite structure. The second initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. Finally, polishing the silicon single crystal film to 220nm to obtain the silicon single crystal film with LN/SiO₂A second composite structure of a stacked structure of/Si.

Next, an indium phosphide wafer having a size of 3 inches was prepared as a raw material substrate. The method of ion implantation is adopted to implant the dose of the InP wafer to be 6 multiplied by 10¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. After ions are implanted into the InP wafer, a thin film layer, a separation layer and a residual material layer are formed. Bonding the thin film layer of the InP wafer with the Si by plasma bonding₃N₄The thin films are bonded to form a third bonded body. And then putting the third bonded body into heating equipment, and preserving heat for 4 hours at 400 ℃ until the thin film layer of the indium phosphide wafer is transferred to the silicon single crystal thin film layer to obtain a third initial composite structure. The third initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. Finally, polishing the film layer of the indium phosphide wafer to 600nm to obtain the indium phosphide-based solar cell with LN/SiO₂A composite film of a/Si/InP stacked structure.

In the composite film including the active layer, the light transmission layer and the light modulation layer obtained by the above method, light emitted from indium phosphide as a self-light emitting material can be transmitted to the silicon layer which is convenient to process into a waveguide and can transmit light, and when the size of the silicon waveguide layer is made sufficiently small, light can be easily transmitted to the silicon oxide layer and then, light is transmitted from the silicon oxide layer to the lithium niobate layer and can be confined in the lithium niobate thin film layer for lateral propagation.

A composite thin film including an active layer, a light transmission layer, and a light modulation layer can be obtained by the above method. Compared with the composite film obtained in embodiment 1, by adding a silica layer between the LN thin film layer and the Si thin film layer, since the silica layer has a lower refractive index than the LN thin film layer and the Si thin film layer, light normally transmitted in the Si thin film layer can be prevented from leaking into the LN thin film layer, and only after the Si thin film layer is reduced in cross-sectional size to a certain extent, light can be transmitted into the LN thin film layer, and therefore, the transmission loss of light in the Si thin film layer can be reduced.

Example 4

Next, a silicon wafer having a size of 3 inches and a thickness of 0.4mm was preparedThe substrate serves as a second substrate, and the silicon wafer substrate has a smooth surface. After the silicon wafer substrate is thoroughly cleaned, SiO with the thickness of 2 mu m is formed on the smooth surface of the silicon wafer substrate by adopting a thermal oxidation method₂And (3) a layer.

Next, an indium phosphide wafer having a size of 3 inches was prepared as a raw material substrate. The method of ion implantation is adopted to implant the dose of the InP wafer to be 6 multiplied by 10¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. After ions are implanted into the InP wafer, a thin film layer, a separation layer and a residual material layer are formed. And bonding the thin film layer of the indium phosphide wafer and the silicon dioxide layer on the silicon wafer serving as the second substrate by a plasma bonding method to form a second bonded body. And then placing the second bonding body into heating equipment, and carrying out heat preservation for 4h at 400 ℃ until the thin film layer of the indium phosphide wafer is transferred to the silicon dioxide layer on the silicon wafer serving as the second substrate to obtain a second initial composite structure. The second initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. And finally, polishing the thin film layer of the indium phosphide wafer to 600nm to obtain a second composite structure.

Next, after the second composite structure was cleaned, Si was formed on the indium phosphide single-crystal thin film to a thickness of 200nm by LPCVD₃N₄A film.

Then, adopting a plasma bonding method to bond the cleaned lithium niobate thin film layer with the first composite structure and the Si layer with the second composite structure₃N₄And bonding the thin surfaces to obtain a third bonded body. Then, the third bond was placed in an oven and incubated at 350 ℃ for 4 h. And then, removing the silicon substrate and the silicon dioxide layer of the second composite structure by adopting dry etching to prepare the composite film.

The silicon nitride layer prepared by LPCVD has a smaller H content than the silicon nitride layer prepared by PECVD, and thus optical transmission loss can be reduced, compared to the method described in embodiment 2.

Example 5

Silicon with a size of 3 inches and a thickness of 0.4mm was preparedThe wafer substrate, and the silicon wafer substrate has a smooth surface. After the silicon wafer substrate is thoroughly cleaned, SiO with the thickness of 2 mu m is formed on the smooth surface of the silicon wafer substrate by adopting a thermal oxidation method₂And (3) a layer.

Next, a silicon wafer having a size of 3 inches and a thickness of 0.4mm was prepared as a light transmission material substrate. After the silicon wafer substrate is thoroughly cleaned, SiO with the thickness of 2 mu m is formed on the smooth surface of the silicon wafer substrate by adopting a thermal oxidation method₂And (3) a layer. Then, the silicon wafer is implanted with the dose of 6 × 10 by adopting the ion implantation method¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. After ions are implanted into a silicon wafer, a thin film layer, a separation layer, and a residual material layer are formed. And bonding the silicon dioxide layer on the thin film layer of the silicon wafer and the lithium niobate single crystal thin film layer by a plasma bonding method to form a second bonding body. And then placing the second bonding body into heating equipment, and preserving heat for 4h at 400 ℃ until the thin film layer of the silicon wafer is transferred to the lithium niobate single crystal thin film layer to obtain a second initial composite structure. The second initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. Finally, polishing the silicon single crystal film to 220nm to obtain the silicon single crystal film with LN/SiO₂A second composite structure of a stacked structure of/Si.

Next, an indium phosphide wafer having a size of 3 inches was prepared as a raw material substrate. The method of ion implantation is adopted to implant the dose of the InP wafer to be 6 multiplied by 10¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. After ions are implanted into the InP wafer, a thin film layer, a separation layer and a residual material layer are formed. And bonding the thin film layer of the indium phosphide wafer and the silicon single crystal thin film by a plasma bonding method to form a third bonded body. And then putting the third bonded body into heating equipment, and preserving heat for 4 hours at 400 ℃ until the thin film layer of the indium phosphide wafer is transferred to the silicon single crystal thin film layer to obtain a third initial composite structure. The third initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. Finally, polishing the film layer of the indium phosphide wafer to 600nm to obtain the indium phosphide-based solar cell with LN/SiO₂A composite film of a/Si/InP stacked structure.

The second isolation layer makes the silicon oxide layer prepared by thermal oxidation, which is prepared by a thermal oxidation method, have a smaller H content than the silicon oxide layer prepared by PECVD, compared to the composite thin film obtained in example 3, and thus can reduce the transmission loss of light.

After the above composite thin film is obtained, a corresponding photoelectric device may be formed using an etching process, a deposition process, a photolithography process, and the like, and an example of manufacturing a photoelectric device using the above composite thin film according to an embodiment of the present disclosure will be described below with reference to embodiment 6.

Example 6

Next, an indium phosphide wafer having a size of 3 inches was prepared as a raw material substrate. The method of ion implantation is adopted to implant the dose of the InP wafer to be 6 multiplied by 10¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. Implanting ions into the InP wafer to form a deviceComprises a film layer, a separation layer and a residual material layer. And bonding the thin film layer of the indium phosphide wafer and the silicon dioxide layer of the silicon substrate by a plasma bonding method to form a first bonding body. And then placing the first bonding body into heating equipment, and carrying out heat preservation for 4h at 400 ℃ until the thin film layer of the indium phosphide wafer is transferred to the silicon dioxide layer to obtain a first initial composite structure. And then, polishing the indium phosphide single-crystal thin film layer to 600nm to obtain a first composite structure of the indium phosphide single-crystal thin film with the nanoscale thickness.

Next, a lithium niobate wafer having a size of 3 inches was prepared as an electro-optical material substrate. The implantation dosage of the lithium niobate wafer is 4 multiplied by 10 by adopting an ion implantation method¹⁶ions/cm²Helium ion (He)¹⁺) And the implantation energy is 200 keV. And implanting ions into the lithium niobate wafer to form a thin film layer, a separation layer and a residual material layer. And bonding the thin film layer of the lithium niobate wafer and the indium phosphide single crystal thin film layer by a plasma bonding method to form a second bonding body. And then placing the second bonding body into heating equipment, and carrying out heat preservation for 4h at 350 ℃ until the thin film layer is transferred to the indium phosphide single crystal thin film layer to obtain a second initial composite structure. And polishing the lithium niobate thin film layer to 400nm by using a Chemical Mechanical Polishing (CMP) method to obtain a second composite structure with an indium phosphide (InP)/Lithium Niobate (LN) stacked structure.

Next, a silicon wafer having a size of 3 inches and a thickness of 0.4mm was prepared as a light transmission material substrate. After the silicon wafer substrate is thoroughly cleaned, SiO with the thickness of 2 mu m is formed on the smooth surface of the silicon wafer substrate by adopting a thermal oxidation method₂And (3) a layer. Then, the silicon wafer is implanted with the dose of 6 × 10 by adopting the ion implantation method¹⁶ions/cm²Hydrogen ion (H) of⁺) And the implantation energy is 100 keV. After ions are implanted into a silicon wafer, a thin film layer, a separation layer, and a residual material layer are formed. And bonding the silicon dioxide layer on the thin film layer of the silicon wafer and the lithium niobate single crystal thin film layer by a plasma bonding method to form a third bonded body. Then the third bonding body is put into heating equipment, and heat preservation is carried out for 4 hours at 400 ℃ until the thin film layer of the silicon wafer is transferred to the niobic acidA lithium single crystal thin film layer to obtain a third initial composite structure. The third initial composite structure was then placed in an oven at 500 ℃ for 4h to eliminate the injection damage. Finally, polishing the silicon single crystal film to 220nm to obtain the silicon single crystal film with InP/LN/SiO₂A third composite structure of a stacked structure of/Si.

And etching the optical thin film layer in the structure by using an ICP (inductively coupled plasma) process so as to form a preset pattern on the optical thin film layer. Then, an electrode is prepared on the preset pattern of the optical thin film layer by utilizing the processes of deposition, photoetching and the like, and then the M-Z modulation device is obtained.

In the embodiment according to the present disclosure, the composite thin film including the active layer, the light transmission layer, and the light modulation layer may be easily obtained by the above-described method. In the embodiment according to the present disclosure, since the light transmission layer formed of a conventional optical waveguide material and the light modulation layer formed of an electro-optical crystal such as lithium niobate are combined to form a composite film applied to an electro-optical device, a complicated process for processing lithium niobate can be avoided, and thus industrial production of an electro-optical device including an electro-optical crystal such as lithium niobate can be realized. In an embodiment according to the present disclosure, the first isolation layer may be a stacked structure in which layers having different refractive indices from each other are alternately stacked, so that a quantum well may be formed between the optical thin film structure and the substrate to reflect light leaked from the optical thin film structure back to the optical thin film structure, thereby reducing optical loss. In an embodiment according to the present disclosure, substrate warpage is improved by forming a compensation layer on a bottom surface of a substrate such that stresses applied to both faces of the substrate cancel each other out.

Although the optical waveguide integrated device according to the exemplary embodiment of the present disclosure is described above with reference to the drawings, the present disclosure is not limited thereto. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure.

Claims

1. A composite film, comprising:

a substrate;

a first isolation layer on a top surface of the substrate;

an optical thin film structure on the first isolation layer and including a stacked structure formed of a light modulation layer, a light transmission layer, and an active layer generating light,

wherein the active layer is in contact with one of the light modulation layer and the light transmission layer.

2. The composite film of claim 1, wherein in the optical film structure, the light modulation layer is disposed on the first spacer layer, the light transmission layer is disposed on the light modulation layer, and the active layer is disposed on the light transmission layer.

3. The composite film of claim 1, wherein in the optical film structure, the active layer is disposed on the first isolation layer, the light transmission layer is disposed on the active layer, and the light modulation layer is disposed on the light transmission layer.

4. The composite film of claim 1 wherein the optical film structure further comprises a second spacer layer between the light transmissive layer and the light modulating layer.

5. The composite film of claim 1 further comprising a compensation layer on a bottom surface of the substrate opposite the top surface,

wherein the compensation layer is of the same material as the first isolation layer.

6. The composite film of claim 1, wherein the first barrier layer is a single layer structure or a multi-layer structure.

7. The composite film according to claim 6, wherein when the first isolation layer is a multilayer structure, the first isolation layer comprises a stacked structure formed by alternately stacking silicon oxide and silicon nitride.

8. The composite film of claim 1, wherein the light modulating layer comprises lithium niobate, lithium tantalate, KDP, DKDP, or quartz.

9. The composite film of claim 1, wherein the light wave transmitting layer comprises silicon or silicon nitride.

10. The composite film as claimed in claim 1, wherein the active layer is formed of at least one of GaN, GaAs, GaSb, InP, AlAs, AlGaAs, AlGaAsP, GaAsP, and InGaAsP.

11. A method of manufacturing a composite film, the method comprising:

depositing a first isolation layer on an upper surface of a first substrate; and

an optical thin film layer is formed on the first spacer layer,

wherein the optical thin film layer includes a stacked structure formed of a light modulation layer, a light transmission layer, and an active layer generating light, the active layer being in contact with one of the light modulation layer and the light transmission layer.

12. The method of claim 11, wherein the step of forming the optical thin film layer on the first spacer layer comprises: the light modulation layer, the light transmission layer and the active layer of the optical thin film layer are formed by an ion implantation process and a wafer bonding process, respectively.

13. The method of claim 12, wherein the optical thin film layer further comprises a second spacer layer between the light modulation layer and the light transmission layer, the second spacer layer being formed by performing a thermal oxidation process on the substrate for forming the light transmission layer.

14. The method of claim 11, wherein the step of forming the optical thin film layer on the first spacer layer comprises: the light modulation layer and the active layer are formed using an ion implantation process and a wafer bonding process, respectively, and the light transmission layer is formed using a deposition process.

15. The method of claim 14, wherein the light transmission layer is formed by LPCVD.