CN114566867A - Transistor laser and preparation method thereof - Google Patents

Transistor laser and preparation method thereof Download PDF

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Publication number
CN114566867A
CN114566867A CN202210195349.XA CN202210195349A CN114566867A CN 114566867 A CN114566867 A CN 114566867A CN 202210195349 A CN202210195349 A CN 202210195349A CN 114566867 A CN114566867 A CN 114566867A
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material layer
emitter
base
layer
component
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梁松
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Institute of Semiconductors of CAS
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Institute of Semiconductors of CAS
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/20—Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers
    • H01S5/2054—Methods of obtaining the confinement
    • H01S5/2059—Methods of obtaining the confinement by means of particular conductivity zones, e.g. obtained by particle bombardment or diffusion
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/20—Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers
    • H01S5/2004—Confining in the direction perpendicular to the layer structure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S2304/00—Special growth methods for semiconductor lasers

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  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optics & Photonics (AREA)
  • Bipolar Transistors (AREA)

Abstract

The present disclosure provides a transistor laser and a method for manufacturing the same, the transistor laser including: a substrate; a collector layer material layer, a base electrode high Al component material layer, a quantum well material layer, an emitter high Al component material layer and an emitter material layer are sequentially grown on the substrate; the emitter material layer, the emitter high Al component material layer, the quantum well material layer and the base high Al component material layer are etched to form an emitter waveguide; the base electrode is arranged on the base material layer and is not connected with the emitter waveguide; the emitter electrode is arranged on the emitter material layer; the collector is arranged on the lower surface of the substrate; wherein, at least one layer of the base high Al component material layer and the emitter high Al component material layer is oxidized in the area close to the two side walls of the emitter waveguide. The transistor laser can effectively reduce the adverse effect of the non-radiative recombination centers on the side wall of the emitter waveguide, thereby remarkably improving the performance of the transistor laser.

Description

Transistor laser and preparation method thereof
Technical Field
The present disclosure relates to the field of optoelectronic device technologies, and in particular, to a transistor laser and a method for manufacturing the same.
Background
A transistor laser is a transistor having both a current control function of the transistor and a light emitting function of the laser. Transistor lasers can simultaneously achieve an electrical signal output (collector current) and an optical signal output with one electrical signal input (e.g., base current). Based on the functional characteristics, the optical fiber has important potential application value in the fields of optical communication, optical signal processing and the like.
In the deep ridge transistor laser structure, the etching of the emitter ridge waveguide passes through the base material under which the quantum well material stops, the quantum well is exposed at the side wall of the base waveguide, a large number of defects exist on the surface of the quantum well, the quantum well is an efficient non-radiative recombination center, a large number of injected carriers are consumed, and the photoelectric performance of the device can be remarkably deteriorated. Experiments show that the influence of quantum well surface defects is still significant even though chemical passivation measures are taken in device manufacturing.
Disclosure of Invention
In view of the above problems, the present invention provides a transistor laser and a method for fabricating the same to solve the above technical problems.
One aspect of the present disclosure provides a transistor laser, comprising: the emitter comprises a substrate, a collector layer material layer, a base electrode high Al component material layer, a quantum well material layer, an emitter high Al component material layer, an emitter material layer, a base electrode, an emitter electrode and a collector; the collector layer material layer, the base electrode high Al component material layer, the quantum well material layer, the emitter high Al component material layer and the emitter material layer are sequentially grown on the substrate; the emitter material layer, the emitter high Al component material layer, the quantum well material layer and the base high Al component material layer are etched to form an emitter waveguide; the base electrode is arranged on the base material layer and is not connected with the emitter waveguide; the emitter electrode is arranged on the emitter material layer; the collector is arranged on the lower surface of the substrate; and at least one of the base high-Al component material layer and the emitting high-Al component material layer is oxidized in a region close to two side walls of the emitting electrode waveguide.
According to an embodiment of the present disclosure, at least one of the base extremely high Al composition material layer and the emitting extremely high Al composition material layer has an Al element content higher than the other material layers.
According to an embodiment of the present disclosure, the non-oxidized region of the base very high Al composition material layer and/or the emitting very high Al composition material layer constitutes a current channel of the transistor laser.
According to an embodiment of the present disclosure, the oxidized region of the base very high Al composition material layer and/or the emission very high Al composition material layer is not conductive.
According to the embodiment of the disclosure, the material of the substrate is InP, the material of the collector layer material layer is InGaAsP or In (1-x-y) GaxAlyAs, the material of the base ultra-high Al component material layer is In (1-x-y) GaxAlyAs, the material of the quantum well material layer is InGaAsP or In (1-x-y) GaxAlyAs, the material of the emitter ultra-high Al component material layer is In (1-x-y) GaxAlyAs, and the material of the emitter material layer is InP.
Another aspect of the present disclosure provides a method of fabricating a transistor laser, the method comprising: sequentially growing a collector layer material layer, a base electrode high Al component material layer, a quantum well material layer, an emitter high Al component material layer and an emitter material layer on a substrate; etching the emitter material layer, the emitter high Al component material layer, the quantum well material layer and the base high Al component material layer to form an emitter waveguide; laterally oxidizing at least one of the base extremely high Al component material layer and the emitting extremely high Al component material layer to be close to the areas of the two side walls of the emitting electrode waveguide; and manufacturing a base electrode on the base material layer, wherein the base electrode is not connected with the emitter waveguide, manufacturing an emitter electrode on the emitter material layer, and manufacturing a collector on the lower surface of the substrate to obtain the transistor light emitter.
The at least one technical scheme adopted in the embodiment of the disclosure can achieve the following beneficial effects:
according to the transistor laser, the current channel is formed by selectively oxidizing Al-containing materials on two sides of the emitter waveguide, the flow of carriers is limited in the central area of the emitter waveguide, the adverse effect of the non-radiative recombination center on the side wall of the emitter waveguide can be effectively reduced, and therefore the performance of the transistor laser is remarkably improved.
Drawings
For a more complete understanding of the present disclosure and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
fig. 1 schematically illustrates a half-cross-sectional structural diagram of a transistor laser provided in an embodiment of the present disclosure;
fig. 2 schematically illustrates a cross-sectional structural diagram of a transistor laser provided in an embodiment of the present disclosure;
fig. 3 schematically illustrates a flowchart of a method for manufacturing a transistor laser according to an embodiment of the present disclosure.
Description of reference numerals:
a substrate-10; a collector layer material layer-20; a base material layer-30; a base ultra high Al component material layer-40; quantum well material layer-50; emitting a layer of a very high Al component material-60; an emitter material layer-70; emitter waveguide-90; oxidized material region-80.
Detailed Description
Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood that the description is illustrative only and is not intended to limit the scope of the present disclosure. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the disclosure. It may be evident, however, that one or more embodiments may be practiced without these specific details. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present disclosure.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The terms "comprises," "comprising," and the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.
All terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. It is noted that the terms used herein should be interpreted as having a meaning that is consistent with the context of this specification and should not be interpreted in an idealized or overly formal sense.
The crystal light laser provided by the embodiment of the present disclosure includes a substrate 10, a collector layer material layer 20, a base material layer 30, a base high Al component material layer 40, a quantum well material layer 50, an emitter high Al component material layer 60, an emitter material layer 70, a base electrode, an emitter electrode, and a collector. A collector layer material layer 20, a base material layer 30, a base high Al component material layer 40, a quantum well material layer 50, an emitter high Al component material layer 60 and an emitter material layer 70 are sequentially grown on the substrate 10; the emitter material layer 70, the emitter high-Al component material layer 60, the quantum well material layer 50 and the base high-Al component material layer 40 are etched to form an emitter waveguide 90; the base electrode is arranged on the base material layer 30 and is not connected with the emitter waveguide 90; the emitter electrode is disposed on the emitter material layer 70; the collector is arranged on the lower surface of the substrate 10; wherein, at least one of the base high Al component material layer 40 and the emitter high Al component material layer 60 is oxidized in the region close to the two side walls of the emitter waveguide 90.
In the present embodiment, at least one of the base high Al composition material layer 40 and the emitter high Al composition material layer 60 has a higher Al element content than the other material layers, and is more easily oxidized than the other material layers. When the Al element content in the base extremely high Al composition material layer 40 is high, only the regions of both sides of the base extremely high Al composition material layer 40 near the side wall of the emitter waveguide 90 may be oxidized; when the Al element content in the emission extremely high Al composition material layer 60 is high, only the regions on both sides of the emission extremely high Al composition material layer 60 near the side wall of the emitter waveguide 90 may be oxidized; when the Al element contents in the base extremely high Al component material layer 40 and the emission extremely high Al component material layer 60 are both high, it is possible to select regions on both sides of the base extremely high Al component material layer 40 and the emission extremely high Al component material layer 60 which are simultaneously oxidized.
The oxidized region of the base very high Al composition material layer 40 and/or the emission very high Al composition material layer 60 is not conductive. Through the oxidation-based extremely high Al component material layer 40 and/or the emission-based extremely high Al component material layer 60, a current channel can be formed in the emission electrode waveguide 90 in a region corresponding to a non-oxidation region of the oxidation-based extremely high Al component material layer 40 and/or the emission-based extremely high Al component material layer 60, so that current carriers can only flow in the current channel and are far away from non-radiative recombination defects on the side wall of the emission electrode waveguide 90, and the adverse effect of the defects on the device performance is reduced.
Fig. 1 and 2 schematically illustrate a half-section structural diagram and an overall schematic diagram of a transistor laser according to an embodiment of the present disclosure, so as to describe structural components.
As shown in fig. 1 and 2, in one embodiment of the present disclosure, regions of the base high Al composition material layer 40 and the emission high Al composition material layer 60 close to two sidewalls of the emitter waveguide 90 are oxidized, an oxidized material region 80 having a width Wr is formed on two sides of the base high Al composition material layer 40 and the emission high Al composition material layer 60, and the oxidized material region 80 is non-conductive, so that a current channel having a width of 2Wa is formed inside the emitter waveguide 90. Carriers can only flow inside the current channel away from non-radiative recombination defects on the sidewalls of emitter waveguide 90, thereby reducing the adverse effect of defects on device performance.
When the Al component in the base extremely high Al component material layer 4040 and the emitting extremely high Al component material layer 60 is higher than that of the other Al-containing material layer, the oxidized material having the width Wr exists in both the two material layers. When only one of the base extremely high Al composition material layer 40 and the emitting extremely high Al composition material layer 60 has a higher Al composition than the other material layers, the oxidized material having a width Wr exists only in the material layer in which the Al composition is higher.
In one embodiment of the present disclosure, the material of the substrate 10 may be InP, the material of the collector layer material layer 20 may be InGaAsP or In (1-x-y) GaxAlyAs, the material of the base material layer 30 may be InGaAsP or In (1-x-y) GaxAlyAs, the material of the base high Al composition material layer 40 may be In (1-x-y) GaxAlyAs, the material of the quantum well material layer 50 may be InGaAsP or In (1-x-y) GaxAlyAs, the material of the emitter very high Al material layer composition 60 may be In (1-x-y) GaxAlyAs, and the material of the emitter material layer 70 may be InP.
Fig. 3 schematically illustrates a flowchart of a method for manufacturing a transistor laser according to an embodiment of the present disclosure.
As shown in fig. 3, a method for manufacturing a transistor laser according to an embodiment of the present disclosure includes operations S301 to S304.
In operation S301, a collector material layer 20, a base material layer 30, a base high Al composition material layer 40, a quantum well material layer 50, an emitter high Al composition material layer 60, and an emitter material layer 70 are sequentially grown on a substrate 10.
In operation S302, the emitter material layer 70, the emitter very high Al composition material layer 60, the quantum well material layer 50, and the base very high Al composition material layer 40 are etched to form the emitter waveguide 90.
In operation S303, at least one of the lateral oxidation-based extremely high Al composition material layer 40 and the emission extremely high Al composition material layer 60 is adjacent to regions of both side walls of the emitter waveguide 90.
In operation S304, a base electrode is formed on the base material layer 30, the base electrode is not connected to the emitter waveguide 90, an emitter electrode is formed on the emitter material layer 70, and a collector electrode is formed on the lower surface of the substrate 10, thereby obtaining a transistor light emitter.
Referring to fig. 1 and 2, taking an InP substrate as an example, the method operations S301 to S304 of the transistor laser according to the embodiment of the present disclosure are implemented as follows.
In operation S301, a collector layer material layer 20 of InGaAsP or In (1-x-y) GaxAlyAs material, a base material layer 30 of InGaAsP or In (1-x-y) GaxAlyAs material, a base ultra high Al composition material layer 40 of In (1-x-y) GaxAlyAs material, a quantum well material layer 50 of InGaAsP or In (1-x-y) GaxAlyAs material, an emitter ultra high Al composition material layer 60 of In (1-x-y) GaxAlyAs material, and an InP emitter material layer 70 are sequentially grown on an InP substrate 10. Wherein the component y of Al in at least one of the base extremely high Al component material layer 40 and the emitting extremely high Al component material layer 60 is larger than the Al component in the other Al-containing material layers.
In operation S302, the emitter material layer 70, the emitter very high Al composition material layer 60, the quantum well material layer 50, and the base very high Al composition material layer 40 are sequentially etched to form the emitter waveguide 90, with the material etch stopping on the base material 30 or stopping in the base material 30.
In operation S303, the high Al composition material layers 40 and 60 are laterally oxidized. Since the Al content y in the high Al component material layer is higher than that of the other material layer, the oxidation rate of the material is higher than that of the other material layer. The oxidation of the material begins at the ridge waveguide sidewalls and proceeds deep into the ridge waveguide, eventually forming oxidized material regions 80 of width Wr in the high Al composition materials 40 and 60. The oxidized material region 80 is non-conductive, thereby forming a current path of width 2Wa inside the emitter waveguide 90. Carriers can only flow inside the current channel away from non-radiative recombination defects on the sidewalls of emitter waveguide 90, thereby reducing the adverse effect of defects on device performance. When the Al composition in both the base extremely high Al composition material layer 40 and the emitting extremely high Al composition material layer 60 is higher than that of the other Al-containing material layer, the oxidized material having the width Wr exists in both the two material layers. When only one of the base extremely high Al composition material layer 40 and the emitting extremely high Al composition material layer 60 has a higher Al composition than the other material layers, the oxidized material having a width Wr exists only in the material layer in which the Al composition is higher.
In operation S304, the base electrode 31, the emitter electrode 91, and the collector electrode 11 are fabricated.
According to the transistor laser prepared by the method, the Al-containing materials on the two sides of the emitter waveguide 90 are selectively oxidized, so that a current channel is formed in the middle of the emitter waveguide 90, the flow of current carriers is limited in the central area of the emitter waveguide 90, the adverse effect of the non-radiative recombination center on the side wall of the emitter waveguide 90 can be effectively reduced, and the performance of the transistor laser is remarkably improved.
Those skilled in the art will appreciate that various combinations and/or combinations of features recited in the various embodiments and/or claims of the present disclosure can be made, even if such combinations or combinations are not expressly recited in the present disclosure. In particular, various combinations and/or combinations of the features recited in the various embodiments and/or claims of the present disclosure may be made without departing from the spirit or teaching of the present disclosure. All such combinations and/or associations are within the scope of the present disclosure.
While the disclosure has been shown and described with reference to certain exemplary embodiments thereof, 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 as defined by the appended claims and their equivalents. Accordingly, the scope of the present disclosure should not be limited to the above-described embodiments, but should be defined not only by the appended claims, but also by equivalents thereof.

Claims (6)

1. A transistor laser, comprising:
the solar collector comprises a substrate (10), a collector layer material layer (20), a base material layer (30), a base high Al component material layer (40), a quantum well material layer (50), an emitter high Al component material layer (60), an emitter material layer (70), a base electrode, an emitter electrode and a collector;
the collector layer material layer (20), the base material layer (30), the base high Al component material layer (40), the quantum well material layer (50), the emitter high Al component material layer (60) and the emitter material layer (70) are sequentially grown on the substrate (10);
the emitter material layer (70), the emitter high Al component material layer (60), the quantum well material layer (50) and the base high Al component material layer (40) are etched to form an emitter waveguide (90);
the base electrode is arranged on the base material layer (30) and is not connected with the emitter waveguide (90);
the emitter electrode is arranged on the emitter material layer (70);
the collector is arranged on the lower surface of the substrate (10);
wherein at least one of the base extremely high Al composition material layer (40) and the emitter extremely high Al composition material layer (60) is oxidized in regions close to both side walls of the emitter waveguide (90).
2. The transistor laser according to claim 1, characterized in that at least one of the base ultra-high Al composition material layer (40) and the emitting ultra-high Al composition material layer (60) has a higher Al element content than the other material layers.
3. The transistor laser according to claim 1, characterized in that the non-oxidized region of the layer of base very high Al composition material (40) and/or the layer of emitting very high Al composition material (60) constitutes the current channel of the transistor laser.
4. The transistor laser according to claim 1, characterized in that the oxidized region of the layer of base very high Al composition material (40) and/or the layer of emitting very high Al composition material (60) is non-conductive.
5. The transistor laser as claimed In claim 1, wherein the material of the substrate (10) is InP, the material of the collector layer material layer (20) is InGaAsP or In (1-x-y) GaxAlyAs, the material of the base material layer (30) is InGaAsP or In (1-x-y) GaxAlyAs, the material of the base very high Al composition material layer (40) is In (1-x-y) GaxAlyAs, the material of the quantum well material layer (50) is InGaAsP or In (1-x-y) GaxAlyAs, the material of the emitter very high Al composition material layer (60) is In (1-x-y) GaxAlyAs, and the material of the emitter material layer (70) is InP.
6. A method of fabricating a transistor laser, the method comprising:
a collector material layer (20), a base material layer (30), a base high Al component material layer (40), a quantum well material layer (50), an emitter high Al component material layer (60) and an emitter material layer (70) are sequentially grown on a substrate (10);
etching the emitter material layer (70), the emitter high Al component material layer (60), the quantum well material layer (50) and the base high Al component material layer (40) to form an emitter waveguide (90);
laterally oxidizing at least one of the base extremely high Al component material layer (40) and the emitting extremely high Al component material layer (60) in the area close to the two side walls of the emitter waveguide (90);
and manufacturing a base electrode on the base material layer (30), wherein the base electrode is not connected with the emitter waveguide (90), manufacturing an emitter electrode on the emitter material layer (70), and manufacturing a collector on the lower surface of the substrate (10) to obtain the transistor light emitter.
CN202210195349.XA 2022-03-01 2022-03-01 Transistor laser and preparation method thereof Pending CN114566867A (en)

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Application Number Priority Date Filing Date Title
CN202210195349.XA CN114566867A (en) 2022-03-01 2022-03-01 Transistor laser and preparation method thereof

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Application Number Priority Date Filing Date Title
CN202210195349.XA CN114566867A (en) 2022-03-01 2022-03-01 Transistor laser and preparation method thereof

Publications (1)

Publication Number Publication Date
CN114566867A true CN114566867A (en) 2022-05-31

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