Method for fabricating junction lasers having lateral current confinement

Claim 1

A method of fabricating a stripe geometry junction laser comprising the steps of: (a) forming a mesa on a major surface of a monocrystalline semiconductor body of one conductivity type, (b) growing simultaneously a pair of laterally spaced epitaxial layers of the opposite conductivity type on said major surface and contiguous with the side walls of said mesa by means of a liquid phase epitaxial process in which growth nucleation on the top of said mesa is inhibited, and (c) growing a laser structure on said spaced layers and the top of said mesa so that a first pair of laterally spaced blocking p-n junctions separated by said mesa are formed at the interface with said pair of layers.

Claim 2

A method of fabricating a stripe geometry junction laser comprising the steps of: (a) forming a mesa on a major surface of a monocrystalline semiconductor body of one conductivity type, (b) growing simultaneously a pair of laterally spaced epitaxial layers of the opposite conductivity type on said major surface and contiguous with the side walls of said mesa by means of a liquid phase epitaxial process in which growth nucleation on the top of said mesa is inhibited, and (c) growing a laser structure on said spaced layers and the top of said mesa so that a first pair of laterally spaced blocking p-n junctions separated by said mesa are formed at the interface with said pair of layers.

Claim 9

A method of fabricating a stripe geometry junction laser comprising the steps of: (a) forming a stripe mesa on a major surface of (100) n-type GaAs substrate, (b) growing simultaneously a pair of laterally spaced p-AlGaAs layers on said major surface and contiguous with the side walls of said mesa by means of a liquid phase epitaxy process in which growth nucleation on the top of said mesa is inhibited, (c) epitaxially growing an n-Al x Ga 1-x As first cladding layer on said spaced layers and the top of said mesa so that a first pair of blocking p-n junctions separated by said mesa are formed at the interface with said pair of layers, (d) epitaxially growing an Al y Ga 1-y As active layer on said first cladding layer, (e) epitaxially growing a p-Al z Ga 1-z As second cladding layer on said active layer so that 0 <x,z; y <x,z; 0 ≦y ≲0.4 and steps (c), (d) and (e) form a double heterostructure laser configuration, (f) epitaxially growing a p-GaAs stop-etch and contacting layer on said second cladding layer, (g) epitaxially growing an n-AlGaAs layer on said p-GaAs layer so as to form a blocking p-n junction at the interface therebetween, (h) forming on said n-AlGaAs layer of step (g) an oxide layer which is resistant to a subsequent etching step, (i) opening a stripe window in said oxide layer in substantial alignment with said mesa, (j) subjecting said n-AlGaAs layer of step (g) to a selective etchant which attacks said layer in said window but not said mask, and which forms a stripe opening in said n-AlGaAs layer but stops etching at said interface with said p-GaAs layer, thereby bifurcating said n-AlGaAs layer and bifurcating said junction of step (g) into a second pair of laterally spaced blocking p-n junctions separated by said opening, (k) removing the remaining portions of said oxide layer, (l) forming an electrode on a free major surface of said substrate, and (m) forming an electrode on said bifurcated n-AlGaAs layer and the portion of said p-GaAs layer exposed by said opening.

Claim 10

A method of fabricating a stripe geometry junction laser comprising the steps of: (a) forming a stripe mesa on a major surface of (100) n-type GaAs substrate, (b) growing simultaneously a pair of laterally spaced p-AlGaAs layers on said major surface and contiguous with the side walls of said mesa by means of a liquid phase epitaxy process in which growth nucleation on the top of said mesa is inhibited, (c) epitaxially growing an n-Al x Ga 1-x As first cladding layer on said spaced layers and the top of said mesa so that a first pair of blocking p-n junctions separated by said mesa are formed at the interface with said pair of layers, (d) epitaxially growing an Al y Ga 1-y As active layer on said first cladding layer, (e) epitaxially growing a p-Al z Ga 1-z As second cladding layer on said active layer so that 0 <x,z; y <x,z; 0 ≦y ≲0.4 and steps (c), (d) and (e) form a double heterostructure laser configuration, (f) epitaxially growing a p-GaAs stop-etch and contacting layer on said second cladding layer, (g) epitaxially growing an n-AlGaAs layer on said p-GaAs layer so as to form a blocking p-n junction at the interface therebetween, (h) forming on said n-AlGaAs layer of step (g) an oxide layer which is resistant to a subsequent etching step, (i) opening a stripe window in said oxide layer in substantial alignment with said mesa, (j) subjecting said n-AlGaAs layer of step (g) to a selective etchant which attacks said layer in said window but not said mask, and which forms a stripe opening in said n-AlGaAs layer but stops etching at said interface with said p-GaAs layer, thereby bifurcating said n-AlGaAs layer and bifurcating said junction of step (g) into a second pair of laterally spaced blocking p-n junctions separated by said opening, (k) removing the remaining portions of said oxide layer, (l) forming an electrode on a free major surface of said substrate, and (m) forming an electrode on said bifurcated n-AlGaAs layer and the portion of said p-GaAs layer exposed by said opening.