CN120813069A - Optoelectronic component - Google Patents

Abstract

A photovoltaic component comprises a substrate, a buffer layer disposed on the substrate and made of the same material as the substrate, an interface layer formed on the buffer layer and made of a working material having an initial internal stress value, a strain layer formed on the interface layer using the working material, an active layer formed on the strain layer and having the initial internal stress value, and a window layer disposed on the active layer and defining an inlet for light to enter the active layer. The strain layer includes a compression-resistant portion attached to the interface layer and having an internal stress value that is a positive proportional value greater than the initial internal stress value, and an anti-extension portion attached to the compression-resistant portion and having an internal stress that is a negative proportional value less than the initial internal stress value. The difference between the positive proportional value and the negative proportional value is a set difference, and the set difference is 0.2 to 0.8%.

Description

Optoelectronic component

Technical Field

The present invention relates to semiconductor devices, and more particularly to optoelectronic devices.

Background

Referring to fig. 1, a conventional photodetector 1 is formed by a molecular beam epitaxy process layer by layer, and sequentially includes a substrate 11, a buffer layer 12 formed on the substrate 11, a quantum well layer 13 formed on the buffer layer 12 and used for blocking light energy to generate an electrical signal, an absorption layer 14 formed on the quantum well layer 13 and used for absorbing light energy, and a window layer 15 formed on the absorption layer 14 and used for limiting the light entering range. When the photodetector 1 operates, light irradiates the absorbing layer 14 from the light entering range defined by the window layer 15, and the light energy absorbed by the absorbing layer 14 is transferred to the quantum well layer 13, and an electrical signal corresponding to the absorbed light energy is generated when the quantum well layer 13 receives the light energy and generates energy gap movement in cooperation with energy gap parameters formed by various material components of the quantum well layer 13. Through the generated electric signals, the electric signals can be converted according to a specific formula, so that the effect of detecting targets such as light energy, gas and the like is achieved.

However, the photodetector 1 may need to operate at a lower temperature for detection. However, since the energy gap of the quantum well layer 13 varies with temperature, the spectrum of the photoelectric response (Responsivity) and the effective sensing wavelength also varies. Particularly in a lower temperature environment, the value of the Cut-off Wavelength is reduced, resulting in a change in the Wavelength range that can be detected to produce a response. In this case, not only the detection range of the wavelength of light is affected, but also when the photodetection element 1 is used to detect the gas type, the specific type of gas may not be detected at a low temperature, and thus the detection performance of the photodetection element 1 may be affected.

Disclosure of Invention

The invention aims to provide an optoelectronic component which can prolong the cut-off wavelength and optimize the detection performance.

The invention relates to an optoelectronic component, which comprises a substrate, a buffer layer, an interface layer, a strain layer, an action layer and a window opening layer, wherein the buffer layer is arranged on the substrate and is made of the same material as the substrate, the interface layer is formed on the buffer layer and is made of a working material with an initial internal stress value, the strain layer is formed on the interface layer and is made of the working material, the action layer is formed on the strain layer and is made of the working material with the initial internal stress value, and the window opening layer is arranged on the action layer and is communicated with the action layer and is suitable for an inlet for introducing light.

The strain layer includes a compressive portion attached to the interface layer and having a positive proportion of internal stress values greater than the initial internal stress values, and an anti-elongation portion attached to the compressive portion and having a negative proportion of internal stress values less than the initial internal stress values. The difference between the positive proportion value and the negative proportion value is a set difference, and the set difference is 0.2-0.8%.

The invention relates to a photoelectric component, wherein the set ratio of the thickness of a compression-resistant part to the thickness of an extension-resistant part of a strain layer is 1-4.

The photoelectric component provided by the invention, wherein the working material is gallium arsenide indium.

The material of the substrate and the buffer layer is indium phosphide.

The photoelectric component further comprises a contact layer formed on the window opening layer, wherein the contact layer comprises a plurality of electrode parts which are suitable for being contacted with at least one external component to form connection.

The invention has the beneficial effects that the strain layer is arranged between the interface layer and the action layer, so that the lattice constants between the interface layer and the action layer can be balanced, and the interface layer, the strain layer and the action layer are epitaxially generated, so that line defects are reduced. The compression-resistant part and the extension-resistant part of the strain layer can be properly balanced between compression stress and tensile stress through proper setting difference values, so that the structures of the interface layer, the strain layer and the acting layer forming the spectrum are complete, and the cut-off wavelength of the spectrum can be effectively prolonged through actual test, thereby optimizing the detection performance.

Drawings

FIG. 1 is a schematic diagram illustrating a prior art photodetection element;

FIG. 2 is a schematic diagram illustrating one embodiment of an optoelectronic device according to the present invention;

FIG. 3 is a graph illustrating the technical significance of a strained layer for material matching according to the present embodiment, using band gap versus lattice constant curve data;

FIG. 4 is a spectrum diagram illustrating the spectral patterns of the response and wavelength components of the present embodiment.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and examples.

Referring to fig. 2, an embodiment of the optoelectronic device of the present invention includes a substrate 2, a buffer layer 3 disposed on the substrate 2 and made of the same material as the substrate 2, an interface layer 4 formed on the buffer layer 3 and made of a working material having an initial internal stress value, a strained layer 5 formed on the interface layer 4 and made of the working material, an active layer 6 formed on the strained layer 5 and made of the working material having the initial internal stress value, a window layer 7 disposed on the active layer 6 and defining an inlet 70 communicating with the active layer 6 and adapted to guide light, and a contact layer 8 formed on the window layer 7. It should be noted that, since the present embodiment is formed layer by epitaxy, the initial internal stress value is based on the internal stress accumulated during crystal growth of the interface layer 4, thereby serving as a relative reference of the internal stress.

Specifically, the material of the substrate 2 and the buffer layer 3 is indium phosphide (InP), and the working material is indium gallium arsenide (InGaAs), so that the interface layer 4, the strain layer 5, and the active layer 6 together form a main working structure that absorbs light energy and can generate an electrical signal. The ratio of gallium to indium in the interface layer 4 is adjusted between the buffer layer 3 and the interface layer 4 with different materials, so that the lattice constant values between the buffer layer 3 and the interface layer 4 are continuously connected as much as possible, or excessive variability is avoided, thus reducing stress accumulation in the crystal growth process and reducing the possibility of defects caused by stress release.

Referring to fig. 2 and 3, the strain layer 5 includes a compression-resistant portion 51 attached to the interface layer 4 and having a positive proportion of internal stress greater than the initial internal stress, and an anti-extension portion 52 attached to the compression-resistant portion 51 and having a negative proportion of internal stress less than the initial internal stress. The difference between the positive proportion value and the negative proportion value is a set difference value, and the set difference value is 0.2-0.8%. Referring to FIG. 3, considering the materials of GaAs and InP simultaneously, the lattice constant of InP is between GaAs and InAs, so that compressive stress (Compressive) and Tensile stress (Tensile) are required in each layer. Therefore, with the strained layer 5 made of the working material, by the internal stress value of the pressure-resistant portion 51 being larger than the positive proportion of the initial internal stress value, excessive compressive stress can be avoided thereby, while the internal stress value of the delay-resistant portion 52 being smaller than the negative proportion of the initial internal stress value, excessive tensile stress can be avoided when joined to the active layer 6. Therefore, the strain layer 5 can form a center of compressive stress and tensile stress, and defects caused by stress release in the process of layer-by-layer epitaxy in the embodiment are avoided.

Specifically, the positive proportion of the compressive portion 51 of the strained layer 5 greater than the initial internal stress value is +0.26 (0.26% increase), the negative proportion of the compressive portion 51 of the strained layer 5 less than the initial internal stress value is-0.50 (0.5% decrease), and in another embodiment, the positive proportion of the compressive portion 51 of the strained layer 5 greater than the initial internal stress value is +0.40, and the negative proportion of the compressive portion 52 less than the initial internal stress value is-0.36. In addition, in terms of the thickness of the pressure-resistant portion 51 and the thickness of the anti-extension portion 52, a set ratio between the thickness of the pressure-resistant portion 51 and the thickness of the anti-extension portion 52 is 1 to 4. Specifically, taking the thickness of the strain layer 5 as 100 nm as an example, the thickness of the compressive portion 51 and the thickness of the anti-stretching portion 52 may both be 50 nm, or a configuration is adopted in which the thickness of the compressive portion 51 is 80 nm and the thickness of the anti-stretching portion 52 is 20 nm.

The window layer 7 is mainly formed with the inlet 70, and a corresponding electrical signal can be generated after the working material absorbs the light energy as long as the light irradiates from the inlet 70. The electric signal can be used for obtaining a required detection result only through specific conversion.

The contact layer 8 includes a plurality of electrode portions 81 adapted to contact an external component to form a connection. The external component is specifically a device capable of reading an electrical signal to convert the electrical signal, and after the electrical connection between the electrode portion 81 and the external component is achieved, the electrical signal generated by receiving the optical energy by the interface layer 4, the strain layer 5, and the active layer 6 is transmitted to the external component.

Table 1:

Referring to fig. 4 in combination with fig. 2, if the use requirement of detecting a specific kind of gas at a lower temperature is taken as an example in this embodiment, the cut-off wavelength needs to be extended to 1800 nm to exert the required detection effect. In this example, after balancing the internal stress by the strained layer 5, the reduction of structural defects was clearly seen, in practice, by microscopic observation, and furthermore, the behavior of dark current was actually measured, meeting the criteria of dark current of less than 1 nanoampere (nA) at 5 volts at each location (see table 1). From the spectrum presented in fig. 4, it is evident that the cut-off wavelength of the present embodiment is near 1800 nm in terms of practical performance, and that the present embodiment does provide better detection performance.

Claims (5)

1. An optoelectronic assembly, characterized in that the optoelectronic assembly comprises:

A substrate;

the buffer layer is arranged on the substrate and is made of the same material as the substrate;

The interface layer is formed on the buffer layer and is made of a working material with an initial internal stress value;

The strain layer is formed on the interface layer and made of the working material, and comprises a compression-resistant part attached to the interface layer and provided with a positive proportion value with an internal stress value larger than the initial internal stress value, and an anti-extension part attached to the compression-resistant part and provided with a negative proportion value with an internal stress smaller than the initial internal stress value, wherein the difference between the positive proportion value and the negative proportion value is a set difference value, and the set difference value is 0.2-0.8%;

An active layer formed on the strained layer and made of the working material having the initial internal stress value, and

The window opening layer is arranged on the acting layer and defines an inlet communicated with the acting layer and suitable for guiding light.

2. The photovoltaic module according to claim 1, wherein the set ratio between the thickness of the compressive portion and the thickness of the tensile portion of the strained layer is 1 to 4.

3. The optoelectronic assembly as claimed in claim 1 or 2, wherein the working material is gallium indium arsenide.

4. The photovoltaic device according to claim 3, wherein the substrate and the buffer layer are made of indium phosphide.

5. The photovoltaic module of claim 1, further comprising a contact layer formed on the fenestration layer, wherein the contact layer comprises a plurality of electrode portions adapted to contact at least one external component to form a connection.