GB1564908A - Solid state lasers - Google Patents

Solid state lasers Download PDF

Info

Publication number
GB1564908A
GB1564908A GB486776A GB486776A GB1564908A GB 1564908 A GB1564908 A GB 1564908A GB 486776 A GB486776 A GB 486776A GB 486776 A GB486776 A GB 486776A GB 1564908 A GB1564908 A GB 1564908A
Authority
GB
United Kingdom
Prior art keywords
layer
solid state
substrate
state laser
elongated
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB486776A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Plessey Co Ltd
Original Assignee
Plessey Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Plessey Co Ltd filed Critical Plessey Co Ltd
Priority to GB486776A priority Critical patent/GB1564908A/en
Publication of GB1564908A publication Critical patent/GB1564908A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/02—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
    • H01L33/20—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a particular shape, e.g. curved or truncated substrate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/0004—Devices characterised by their operation
    • H01L33/002—Devices characterised by their operation having heterojunctions or graded gap
    • H01L33/0025—Devices characterised by their operation having heterojunctions or graded gap comprising only AIIIBV compounds
    • 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
    • H01S5/22—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 having a ridge or stripe structure
    • H01S5/227—Buried mesa structure ; Striped active layer
    • 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
    • H01S5/30—Structure or shape of the active region; Materials used for the active region
    • H01S5/32—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures
    • 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
    • H01S5/22—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 having a ridge or stripe structure
    • H01S5/227—Buried mesa structure ; Striped active layer
    • H01S5/2275—Buried mesa structure ; Striped active layer mesa created by etching

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optics & Photonics (AREA)
  • Geometry (AREA)
  • Semiconductor Lasers (AREA)

Description

(54) IMPROVEMENTS IN OR RELATING TO SOLID STATE LASERS (71) We, THE PLESSEY COMPANY LIMImD, a British Company of 2/60 Vicarage Lane, Ilford, Essex, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to improvements in or relating to solid state lasers and to methods of producing same.
According to the invention there is provided a solid state laser including an indium phosphide body; and an elongated gallium indium arsenide phosphide member which is of opposite conductivity type to at least part of the said body and thereby forms a P-N junction therewith and which is partially enclosed within the said body, the free ends of the elongated member emerging at separate surfaces of the said body.
According to a feature of the invention a solid state laser as outlined in the preceding paragraph is provided wherein the said body is in two parts which are of opposite conductivity types to each other.
According to another feature of the invention a solid state laser as outlined in the preceding paragraph is provided which comprises an indium phosphide substrate of N type conductivity that forms one part of the said body; an elongated gallium indium arsenide phosphide member of P type conductivity which is formed on a major surface of the substrate and thereby forms a P-N junction therewith; a layer of indium phosphide of P type conductivity which forms the other part of the said body and which partially encloses the said member, the free ends of the said elongated member emerging at separate surfaces of the said body; a first contact layer formed on that surface of the substrate which is opposite to the said major surface thereof; a second contact layer formed on a surface of the P type indium phosphide layer, the said elongated member being situated between the contact layers: and a heat sink secured to the second contact layer.
According to the invention there is also provided a method of producing a solid state laser which includes the steps of providing an indium phosphide substrate of a first conductivity type; forming an elongated gallium indium arsenide phosphide member of opposite conductivity type to the substrate on a major surface of the substrate such that a P-N junction is formed therebetween; forming a layer of indium phosphide of the same conductivity type as the elongated member on the said major surface of the substrate so that the elongated member is partially enclosed thereby, the free ends of the elongated member emerging at separate surfaces of an indium phosphide body formed by the substrate and the indium phosphide layer forming a first contact layer on that surface of the said substrate which is opposite to the said major surface thereof; forming a second contact layer on the outer surface of the said indium phosphide layer such that the said elongated member is situated between the first and second contact layers; and securing a heat sink to the second contact layer.
According to a feature of the invention a method of producing a solid state laser as outlined in the preceding paragraph is provided which includes the steps of providing an indium phosphide substrate of a first conductivity type; forming a gallium indium arsenide phosphide layer of opposite conductivity type to the substrate on a major surface of the substrate such that a P-N junction is formed therebetween; selectively removing portions of the gallium indium arsenide phosphide layer to provide a number of spaced-apart, parallel, elongated stripes; forming a layer of indium phosphide of the same conductivity type as the gallium indium arsenide phosphide layer on the said major surface of the substrate so that each of the said elongated stripes are partially enclosed thereby, the free ends of each of the elongated stripes emerging at separate surfaces of the said indium phosphide body P-N junctions being formed situated at the interface of the substrate and the gallium indium arsenide phosphide layer; selectively removing portions of the indium phosphide layer between each of the said elongated stripes to divide the said layer into a number of regions which are each associated with a separate one of the said elongated stripes; forming a first contact layer on that surface of the said substrate which is opposite to the said major surface thereof; forming a second contact layer on each of the separate regions of the said indium phosphide layer such that each of the said elongated stripes are situated between the associated first and second contact layers; applying a heat sink to each of the second contact layers; and forming a number of separate solid state lasers by cutting the said substrate between each of the said elongated stripes, and by cleaving in a direction transverse to the said elongate stripes.
The foregoing and other fefatures according to the invention will be better understood from the following description of preferred embodiments of the invention with reference to the drawings accompanying the Provisional Specification in which: Figure 1 pictorially illustrates a completed solid state laser according to the invention, Figures 2a to 2c diagrammatically illustrate in side elevations various stages in the production of the solid state laser depicted in Figure 1, and Figures 3a to 3e diagrammatically illustrate in side elevations various stages in the production of a number of solid state lasers.
A solid state laser according to the invention will now be discussed with reference to Figure 1 of the drawings.
The solid state laser includes an indium phosphide body, which comprises an indium phosphide substrate 1, of N type conductivity, and an indium phosphide layer 2 of p type conductivity.
A gallium indium arsenide phosphide member 3 which is of an elongated shape, and which is of p type conductivity, is partially enclosed by the indium phosphide body and forms a P-N junction therewith.
The free ends of the member 3 emerge at separate surfaces of the indium phosphide body, P-N junctions being formed at the interface formed between the substrate 1 and the member 3.
A contact layer 4 is formed on a surface la of the substrate 1 and a contact layer 5 is formed on that portion of an upper surface 2a of the layer 2 which is situated directly above the member 3 i.e. the member 3 is situated between the two contact layers 4 and 5.
Formed on a surface Sa of the contact layer 5, is a heat sink 6 which, for example, can be made from gold.
A preferred method of the producing a solid state laser according to the invention wilt now be described with reference to Figures 2a, 2b and 2c of the drawings.
The first stage of the method is shown in Figure 2a and involves the steps of providing an indium phosphide substrate 7 of N type conductivity, and forming on a portion of a major surface 7a thereof an elongated gallium indium arsenide phosphide member 8 of P type conductivity such that a P-N junction is formed therebetween.
The elongated member 8 is, for example, formed on the substrate 7 by vapour or liquid epitaxy, and its thickness would, in practice, be in the range 0.1 to 2.0 microns.
The preferred orientation of the substrate 7 stated in Miller indices is (100) or 2 degrees of (100) towards (110).
A preferred range of conductivity values for the substrate 7, is 5 X 1017 to 5 x 1018 electrons/cm3, and for the elongated members 8, 5 X 1017 to 5 X 1019 holes/cm3.
The next stage of the method is shown in Figure 2b and involves the steps of forming an indium phosphide layer 9 of P type conductivity on the major surface 7a of the substrate 7 such that the elongated member 8 is partially enclosed by the layer 9. The free ends of the elongated member 8 emerge at separate surfaces along the interface between the substrate 7 and the indium phosphide layer 9. The layer 9 can, for example, be formed on the substrate 7 by epitaxial growth. The thickness of the layer 9 is, in practice, in the range 1 to 10 microns.
The next stage of the method which is illustrated in Figure 2c of the drawings, involves the steps of forming contact layers 10 and 11, and a heat sink 12.
The contact layer 10 is formed on a surface 7b of the substrate 7, and the contact layer 11 is formed on that portion of an upper surface 9a of the layer 9 which is situated directly above the elongated member 8, the elongated member 8 being situated between the contact layers 10 and 11. Both contact layers can, for example, be formed by standard metallization techniques.
Lastly a heat sink 12, for example of gold, is formed on a surface 1 lea of the contact layer 11, by for example, a plating process.
A preferred method of producing a number of solid state lasers according to the invention will now be described with reference to Figures 3a to 3e of the drawings.
The first stage of the method is shown in Figure 3a and involoves the steps of providing an indium phosphide substrate 13 of N type conductivity and forming on a major surface 1 3a thereof, a layer 14 of P type gallium indium arsenide phosphide such that a P-N junction is formed therebetween.
The layer 14 can be formed on the substrate 13 by liquid or vapour epitaxy. Suitable dopants for the N type substrate 13, are silicon, sulphur, tellurium and tin, and for the P type layer 14, zinc, cadmium and germanium dopants can be used. The preferred orientntion of the substrate 13 expressed in Miller indicies is (100) or 2 degrees off (100) towards (110). The thickness of the layer 14 is, in practice, in the range 0.1 to 2.0 microns.
The next stage of the method is shown in Figure 3b and involves the steps of selectively removing portions of the gallium indium arsenide phosphide layer 14 to provide a number of spaced-apart, parallel, elongated stripes 15. This can be achieved, for example, by applying a mask of silicon dioxide in the form of stripes 1 to 10 microns wide to a surface 14a of the layer 14. and then etching away, with a suitable etchant, the uncovered portions of the laver 14 to provide the spaced-apart, parallel elongated stripes 15. The silicon dioxide mask is then removed bv applying a suitable solvent, for example, 10% HF/H2O.
The next stane of the method is shown in Figure 3c, and involves the steps of forming an indium phosphide layer 16 of P type conductivity by, for example, epitaxial growth, on the surface 1 3a and 14a. Hence, each elongated stripe 15 is partially enclosed by the layer 16. The free ends of each of the elongated stripes 15 emerge at separate surfaces along the interface between the layer 16 and the substrate 13. By partially enclosing each elongated stripe 15, optical confinement of the radiation generated in each elongated stripe 15 is achieved.
The next stage of the method involves the selective removal of portions of the layer 16 from between each elongated stripe 15, so that excess leakage through the interface between the substrate 13 and the layer 16 is reduced. This can be achieved as is illustrated in Figure 3c, for example, by forming silicon dioxide stripes 17 on the surface of those regions of the layer 16 which are associated with each of the elongated stripes 15. A chemical etch is then used to remove the uncovered portions of the layer 16. The silicon dioxide stripes 17 are then removed so that each elongated stripe 15 is associated with a separate region of the layer 16 as is illustrated in Figure 3d of the drawings.
The next stage of the method is illustrated in Figure 3e of the drawings and involves the steps of forming a contact layer 18 on the surface 13b of the substrate 13, and the formation of a contact layer 19 on each region of the layer 16. The contact layers can, for example, be formed by standard metallization techniques.
A heat sink 20 is then formed on each of the contact layers 19. The heat sinks 20 can, for example, be formed by a plating process and are usually made of gold.
A number of individual solid state lasers can then be formed by first cutting the substrate 13 between each of the elongated stripes 15 along the lines A-A, then cleaving i.e. by cutting in such a way as to leave an optically polished surface, through each of the said elongated stripes in a transverse direction.
The optical confinement of the elongated member as described in preceding paragraphs ensures that the lasing action of the solid state laser is along the longitudinal axis of the elongated member.
Thus a solid state laser according to the invention includes an indium phosphide body, and an elongated gallium indium arsenide phosphide member which is of an opposite conductivity to at least part of the body. The elongated member is at least partially enclosed by the body such that P-N junctions are formed between the elongate member and the body.
The body can also be constructed in two parts. The parts being of opposite or similar conductivity types to each other. The P-N junctions being formed at the interface of the body and the elongated member which is of an opposite conductivity type to at least one part of the body.
The indium phosphide body is preferably formed from parts which possess different conductivity types to each other, however, the body may be formed from parts of one conductivity type, so long as the conductivity type of the elongated member is opposite to that of the body.
The main, but not exclusive, use of the solid state laser is as a light source in fibre optic communication systems. The solid state laser can also be used as a light source in hand held range finding systems.
WHAT WE CLAIM IS:- 1. A solid state laser including an indium phosphide body; and an elongated gallium indium arsenide phosphide member which is of opposite conductivity type to at least part of said body and thereby forms a P-N junction therewith and which is partially enclosed within said body, the free ends of the elongated member emerging at separate surfaces of said body.
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (35)

  1. **WARNING** start of CLMS field may overlap end of DESC **.
    A preferred method of producing a number of solid state lasers according to the invention will now be described with reference to Figures 3a to 3e of the drawings.
    The first stage of the method is shown in Figure 3a and involoves the steps of providing an indium phosphide substrate 13 of N type conductivity and forming on a major surface 1 3a thereof, a layer 14 of P type gallium indium arsenide phosphide such that a P-N junction is formed therebetween.
    The layer 14 can be formed on the substrate 13 by liquid or vapour epitaxy. Suitable dopants for the N type substrate 13, are silicon, sulphur, tellurium and tin, and for the P type layer 14, zinc, cadmium and germanium dopants can be used. The preferred orientntion of the substrate 13 expressed in Miller indicies is (100) or 2 degrees off (100) towards (110). The thickness of the layer 14 is, in practice, in the range 0.1 to 2.0 microns.
    The next stage of the method is shown in Figure 3b and involves the steps of selectively removing portions of the gallium indium arsenide phosphide layer 14 to provide a number of spaced-apart, parallel, elongated stripes 15. This can be achieved, for example, by applying a mask of silicon dioxide in the form of stripes 1 to 10 microns wide to a surface 14a of the layer 14. and then etching away, with a suitable etchant, the uncovered portions of the laver 14 to provide the spaced-apart, parallel elongated stripes 15. The silicon dioxide mask is then removed bv applying a suitable solvent, for example, 10% HF/H2O.
    The next stane of the method is shown in Figure 3c, and involves the steps of forming an indium phosphide layer 16 of P type conductivity by, for example, epitaxial growth, on the surface 1 3a and 14a. Hence, each elongated stripe 15 is partially enclosed by the layer 16. The free ends of each of the elongated stripes 15 emerge at separate surfaces along the interface between the layer 16 and the substrate 13. By partially enclosing each elongated stripe 15, optical confinement of the radiation generated in each elongated stripe 15 is achieved.
    The next stage of the method involves the selective removal of portions of the layer 16 from between each elongated stripe 15, so that excess leakage through the interface between the substrate 13 and the layer
    16 is reduced. This can be achieved as is illustrated in Figure 3c, for example, by forming silicon dioxide stripes 17 on the surface of those regions of the layer 16 which are associated with each of the elongated stripes 15. A chemical etch is then used to remove the uncovered portions of the layer 16. The silicon dioxide stripes 17 are then removed so that each elongated stripe 15 is associated with a separate region of the layer 16 as is illustrated in Figure 3d of the drawings.
    The next stage of the method is illustrated in Figure 3e of the drawings and involves the steps of forming a contact layer 18 on the surface 13b of the substrate 13, and the formation of a contact layer 19 on each region of the layer 16. The contact layers can, for example, be formed by standard metallization techniques.
    A heat sink 20 is then formed on each of the contact layers 19. The heat sinks 20 can, for example, be formed by a plating process and are usually made of gold.
    A number of individual solid state lasers can then be formed by first cutting the substrate 13 between each of the elongated stripes 15 along the lines A-A, then cleaving i.e. by cutting in such a way as to leave an optically polished surface, through each of the said elongated stripes in a transverse direction.
    The optical confinement of the elongated member as described in preceding paragraphs ensures that the lasing action of the solid state laser is along the longitudinal axis of the elongated member.
    Thus a solid state laser according to the invention includes an indium phosphide body, and an elongated gallium indium arsenide phosphide member which is of an opposite conductivity to at least part of the body. The elongated member is at least partially enclosed by the body such that P-N junctions are formed between the elongate member and the body.
    The body can also be constructed in two parts. The parts being of opposite or similar conductivity types to each other. The P-N junctions being formed at the interface of the body and the elongated member which is of an opposite conductivity type to at least one part of the body.
    The indium phosphide body is preferably formed from parts which possess different conductivity types to each other, however, the body may be formed from parts of one conductivity type, so long as the conductivity type of the elongated member is opposite to that of the body.
    The main, but not exclusive, use of the solid state laser is as a light source in fibre optic communication systems. The solid state laser can also be used as a light source in hand held range finding systems.
    WHAT WE CLAIM IS:- 1. A solid state laser including an indium phosphide body; and an elongated gallium indium arsenide phosphide member which is of opposite conductivity type to at least part of said body and thereby forms a P-N junction therewith and which is partially enclosed within said body, the free ends of the elongated member emerging at separate surfaces of said body.
  2. 2. A solid state laser as claimed in claim
    1 wherein said body is in two parts which are each of the same conductivity type; the elongated member being of an opposite conductivity type to the body.
  3. 3. A solid state laser as claimed in claim 1 wherein said body is in two parts which are of opposite conductivity types to each other.
  4. 4. A solid state laser as claimed in claim 3 which comprises an indium phosphide substrate of N type conductivity that forms one part of said body; an elongated gallium indium arsenide phosphide member of P type conductivity which is formed on a major surface of the substrate and thereby forms a P-N junction therewith; a layer of indium phosphide of P type conductivity which forms the other part of said body and which partically encloses said member, the free ends of said elongated member emerging at separate surfaces of said body; a first contact layer formed on that surface of the substrate which is opposite to said major surface thereof; a second contact layer formed on a surface of the P-type indium phosphide layer, said elongated member being situated between the contact layers; and a heat sink secured to the second contact layer.
  5. 5. A solid state laser as claimed in claim 4 wherein the heat sink is constructed from gold.
  6. 6. A method of producing a solid state laser which includes the steps of providing an indium phosphide substrate of a first conductivitv type; forming an elongated gallium indium arsenide phosphide member of opposite conductivity type to the substrate on a maior surface of the substrate such that a P-N junction is formed therebetween, forming a layer of indium phosphide of the same conductivity type as the elongated member on the said major surface of the substrate so that the elongated member is partially enclosed thereby, the free ends of the elongated member emerging at separate surfaces of an indium phosphide body formed by the substrate and the indium nhosphide layer, forming a first contact layer on that surface of the said substrate which is opposite to the said major surface thereof; forming a second contact layer on the outer surface of the said indium phosphide layer such that the said elongated member is situated between the first and second contact layers; and securing a heat sink to the second contact layer.
  7. 7. A method of producing a solid state laser as claimed in claim 6 wherein the elongated member is formed on a major surface of the substrate by vapour enitaxy.
  8. 8. A method of producing a solid state laser as claimed in claim 7 wherein the elongated member is formed on a major surface of the substrate by liquid epitaxy.
  9. 9. A method of producing a solid state laser as claimed in claim 8 wherein the thickness of the elongated member is in the range 0.1 to 2.0 microns.
  10. 10. A method of producing a solid state laser as claimed in claim 9 wherein the orientation of the substrate stated in Miller indices is (100).
  11. 11. A method of producing a solid state laser as claimed in claim 10 wherein the orientation of the substrate stated in Miller indices is 2 degree off (100) towards (110).
  12. 12. A method of producing a solid state laser as claimed in claim 11 wherein the conductivity values for the substrate are in the range 5 X 1017 to 5 x 1018 electrons/ cm3.
  13. 13. A method of producing a solid state laser as claimed in claim 12 wherein the conductivity values for the elongated member are in the range 5 x 1017 to 5 X 1019 holes 1cm3.
  14. 14. A method of producing a solid state laser as claimed in claim 13 wherein the layer of indium phosphide is formed by epitaxial growth.
  15. 15. A method of producing a solid state laser as claimed in claim 14 wherein the thickness of the indium phosphide layer is in the range 1 to 10 microns.
  16. 16. A method of producing a solid state laser as claimed in claim 15 wherein the heat sink is constructed from gold.
  17. 17. A method of producing a solid state laser which includes the steps of providing an indium phosphide substrate of a first conductivity type; forming a gallium indium arsenide phosphide layer of opposite conductivity type to the substrate on a major surface of the substrate such that a P-N junction is formed therebetween; selectively removing portions of the gallium indium arsenide phosphide layer to provide a number of spaced-apart, parallel, elongated stripes; forming a layer of indium phosphide of the same conductivity type as the gallium indium arsenide phosphide layer on the sp r surface of the substrate so that each of the said elongated stripes are partially enclosed thereby, the free ends of each of the elongated stripes emerging at separate surfaces of the said indium phosphide body, P-N junctions being formed at the interface of the substrate and the gallium indium arsenide phosphide layer; selectively removing portions of the indium phosphide layer between each of the said elongated stripes to divide the said layer into a number of regions which are each associated with a separate one of the said elongated stripes; forming a first contact layer on that surface of the said substrate which is opposite to the said major surface thereof: forming a second contact layer on each of the separate regions of the said indium phosphide layer such that each of the said elongated stripes are situated between the associated first and second contact layers; applying a heat sink to each of the second contact layers; and forming a number of separate solid state lasers by cutting the said substrate between each of the said elongated stripes, and by cleaving in a direction transverse to the said elongated stripes.
  18. 18. A method of producing a solid state laser as claimed in claim 17 wherein the gallium indium arsenide phosphide layer is formed on the substrate by liquid epitaxy.
  19. 19. A method of producing a solid state laser as claimed in claim 18 wherein the gallium indium arsenide phosphide layer is formed on the substrate by vapour epitaxy.
  20. 20. A method of producing a solid state laser as claimed in claim 19 wherein dopants for an N-type substrate are selected from a group which includes silicon, sulphur, tellurium and tin.
  21. 21. A method of producing a solid state laser as claimed in claim 20 wherein dopants for a P-type layer are selected from a group which includes zinc, cadmium and germanium.
  22. 22. A method of producing a solid state laser as claimed in claim 21 wherein the orientation of the substrate stated in Miller indices is (100).
  23. 23. A method of producing a solid state laser as claimed in claim 22 wherein the orientation of the substrate stated in Miller indices is 2 degrees off (100) towards (110).
  24. 24. A method of producing a solid state laser as claimed in claim 23 wherein the thickness of the gallium indium arsenide phosphide layer is in the range 0.1 to 2 microns.
  25. 25. A method of producing a solid state laser as claimed in claim 24 wherein selective removal of portions of the gallium indium arsenide phosphide layer is carried out by a method which includes applying a mask of silicon dioxide to a major surface of the gallium indium arsenide phosphide: and etching away uncovered portions of the gallium indium arsenide phosphide with an etchant to form a number of spaced-apart, parallel elongated stripes.
  26. 26. A method of producing a solid state laser as claimed in claim 26 wherein the silicon dioxide mask is removed by application of a solvent.
  27. 27. A method of producing a solid state laser as claimed in claim 26 wherein the solvent is 10% HF/H2O.
  28. 28. A method of producing a solid state laser as claimed in claim 27 wherein selective removal of regions of the indium phosphide layer is carried out by a method which includes applying silicon dioxide stripes to each of those regions of the indium phosphide layer associated with an elongated stripe of gallium indium arsenide phosphide; etching away the uncovered regions of the indium phosphide layer; and removing the silicon dioxide stripes such that each elongated striped gallium indium arsenide phosphide is associated with a separate region of the indium phosphide layer.
  29. 29. A method of producing a solid state laser as claimed in claim 28 wherein the heat sinks are constructed from gold.
  30. 30. A solid state laser substantially as hereinbefore described with reference to and as illustrated in Figure 1 or Figure 2c or Figure 3e of the drawings accompanying the provisional specification.
  31. 31. A solid state laser when produced according to the method as claimed in any one of claims 6 to 16.
  32. 32. A solid state laser when produced according to the method as claimed in any one of claims 17 to 29.
  33. 33. A method of producing a solid state laser substantially as hereinbefore described with reference to and as illustrated in Figures 2a, 2b and 2c of the drawings accompanying the provisional specification.
  34. 34. A method of producing a solid state laser substantially as hereinbefore described with reference to and as illustrated in Figure 3a and 3e of the drawing accompanying the provisional specification.
  35. 35. A fibre optic communication system including a solid state laser as claimed in any one of claims 1 to 5.
GB486776A 1976-02-07 1976-02-07 Solid state lasers Expired GB1564908A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB486776A GB1564908A (en) 1976-02-07 1976-02-07 Solid state lasers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB486776A GB1564908A (en) 1976-02-07 1976-02-07 Solid state lasers

Publications (1)

Publication Number Publication Date
GB1564908A true GB1564908A (en) 1980-04-16

Family

ID=9785318

Family Applications (1)

Application Number Title Priority Date Filing Date
GB486776A Expired GB1564908A (en) 1976-02-07 1976-02-07 Solid state lasers

Country Status (1)

Country Link
GB (1) GB1564908A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2495383A1 (en) * 1980-11-28 1982-06-04 Western Electric Co SUPERRADIANCE ELECTROLUMINESCENT DIODE HAVING HIGH COUPLING EFFICIENCY WITH OPTICAL WAVEGUIDE
EP0087253A1 (en) * 1982-02-24 1983-08-31 Plessey Overseas Limited Improvements in or relating to semi-conductor lasers

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2495383A1 (en) * 1980-11-28 1982-06-04 Western Electric Co SUPERRADIANCE ELECTROLUMINESCENT DIODE HAVING HIGH COUPLING EFFICIENCY WITH OPTICAL WAVEGUIDE
EP0087253A1 (en) * 1982-02-24 1983-08-31 Plessey Overseas Limited Improvements in or relating to semi-conductor lasers
US4542511A (en) * 1982-02-24 1985-09-17 Plessey Overseas Limited Semi-conductor lasers

Similar Documents

Publication Publication Date Title
US3981023A (en) Integral lens light emitting diode
US3349475A (en) Planar injection laser structure
JPS589389A (en) Light emitting structure and method of producing same
KR100582114B1 (en) A method of fabricating a semiconductor device and a semiconductor optical device
JPS6017910Y2 (en) Integral lens light emitting diode structure
US4532694A (en) Method of fabricating emitter/detector-in-a-well for the integration of electronic and optoelectronic components
GB1564908A (en) Solid state lasers
JPH01214089A (en) Method of forming diffraction lattice in semiconductor material and photoelectric device with the diffraction lattice manufactured by the method
KR19980058397A (en) RWG laser diode and its manufacturing method
JPS58220486A (en) Manufacture of semiconductor light emitting element
EP0067586B1 (en) Electro-optic element and method of making the same
JPS6057990A (en) Semiconductor laser
JPS59229891A (en) Manufacture of semiconductor laser
KR100239792B1 (en) Ingaasp/inp bh ld
JPS63209189A (en) Production of semiconductor laser
Andreyev et al. Liquid‐phase epitaxy of AlGaAs heterostructures on profiled substrates
JPS58158988A (en) Distributed feedback type semiconductor laser
JPS6290969A (en) Manufacture of optical integrated circuit
JPS56158495A (en) Manufacture of semiconductor light emitting device
CN117353156A (en) Chip of BH-EML monolithic integrated optical amplifier and preparation method thereof
JPH0377675B2 (en)
KR950012940A (en) Indexed waveguide semiconductor laser diode and method of manufacturing the same
JPS622479B2 (en)
JPS627185A (en) Manufacture of semiconductor laser
JPH0586076B2 (en)

Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee