Abstract:
A GaN compound semiconductor laser includes an AlGaN buried layer which buries opposite sides of a ridge stripe portion formed on a p-type AlGaN cladding layer. The AlGaN buried layer is made by first patterning an upper part of the p-type AlGaN cladding layer and a p-type GaN contact layer into a ridge stripe configuration by using a SiO2 film as an etching mask, then growing the AlGaN buried layer non-selectively on the entire substrate surface to bury both sides of the ridge stripe portion under the existence of the SiO2 film on the ridge stripe portion, and thereafter selectively removing the AlGaN buried layer from above the ridge stripe portion by etching using the SiO2 film as an etching stop layer. Thus, the GaN compound semiconductor laser is stabilized in the transverse mode, intensified in output power, and improved in lifetime.
Abstract:
An ohmic electrode and a process for fabricating the same, said process comprising forming a first metallic layer (14) comprising indium or an indium alloy on a compound semiconductor layer (10), forming a second metallic layer (16) comprising a gold-germanium alloy on said first metallic layer (14), and subjecting the first and the second metallic layer thus obtained to alloying treatment. The present invention provides favorable ohmic contacts by effecting the alloying treatment at a relatively low temperature of 350 DEG C or even lower.
Abstract:
A GaN compound semiconductor laser includes an AlGaN buried layer which buries opposite sides of a ridge stripe portion formed on a p-type AlGaN cladding layer. The AlGaN buried layer is made by first patterning an upper part of the p-type AlGaN cladding layer and a p-type GaN contact layer into a ridge stripe configuration by using a SiO2 film as an etching mask, then growing the AlGaN buried layer non-selectively on the entire substrate surface to bury both sides of the ridge stripe portion under the existence of the SiO2 film on the ridge stripe portion, and thereafter selectively removing the AlGaN buried layer from above the ridge stripe portion by etching using the SiO2 film as an etching stop layer. Thus, the GaN compound semiconductor laser is stabilized in the transverse mode, intensified in output power, and improved in lifetime.
Abstract:
IT IS INTENDED TO PROVIDE A SEMICONDUCTOR DEVICE, ITS MANUFACTURING METHOD AND SUBSTRATE FOR MANUFACTURING THE SEMICONDUCTOR DEVICE WHICH ENSURES THAT GOOD CLEAVABLE SURFACES BE MADE STABLY IN A SEMICONDUCTOR LAYER UNDER PRECISE CONTROL UPON MAKING EDGES OF CLEAVES SURFACES IN THE SEMICONDUCTOR LAYER STACKED ON A SUBSTRATE EVEN WHEN THE SUBSTRATE IS NON-CLEAVABLE, DIFFICULT TO CLEAVE OR DIFFERENT IN CLEAVABLE ORIENTATION FROM THE SEMICONDUCTOR LAYER. A SEMICONDUCTOR LAYER (2) MADE OF III-V COMPOUND SEMICONDUCTORS IS STACKED TO FORM A LASER STRUCTURE ON A SAPPHIRE SUBSTRATE (1). IN SELECTIVE LOCATIONS OTHER THAN THE LOCATION OF A RIDGE STRIPE PORTION (11) AND A MESA PORTION (12) ALONG A PORTION OF A SEMICONDUCTOR LAYER (2) WHERE A CAVITY EDGE (3) SHOULD BE MADE, NAMELY, IN LOCATIONS AT OPPOSITE SIDES OF THE MESA PORTION (12), STRIPE-SHAPED CLEAVAGE-ASSIST GROOVES (4) ARE MADE TO EXTEND IN PARALLEL TO THE (11-20)-ORIENTED SURFACE OF THE SEMICONDUCTOR LAYER (2), AND THE SEMICONDUCTOR LAYER (2) AND THE SAPPHIRE SUBSTRATE (1) ARE CLEAVED FROM THE CLEAVAGE-ASSIST GROOVE (4) TO MAKE THE CAVITY EDGE (3) MADE UP OF THE CLEAVABLE SURFACE OF THE SEMICONDUCTOR LAYER (2).
Abstract:
It is intended to provide a semiconductor device, its manufacturing method and substrate for manufacturing the semiconductor device which ensures that good cleavable surfaces be made stably in a semiconductor layer under precise control upon making edges of cleaves surfaces in the semiconductor layer stacked on a substrate even when the substrate is non-cleavable, difficult to cleave or different in cleavable orientation from the semiconductor layer. A semiconductor layer 2 made of III-V compound semiconductors is stacked to form a laser structure on a sapphire substrate 1. In selective locations other than the location of a ridge stripe portion 11 and a mesa portion 12 along a portion of a semiconductor layer 2 where a cavity edge 3 should be made, namely, in locations at opposite sides of the mesa portion 12, stripe-shaped cleavage-assist grooves 4 are made to extend in parallel to the (11-20)-oriented surface of the semiconductor layer 2, and the semiconductor layer 2 and the sapphire substrate 1 are cleaved from the cleavage-assist groove 4 to make the cavity edge 3 made up of the cleavable surface of the semiconductor layer 2.
Abstract:
An ohmic electrode and a process for fabricating the same, said process comprising forming a first metallic layer (14) comprising indium or an indium alloy on a compound semiconductor layer (10), forming a second metallic layer (16) comprising a gold-germanium alloy on said first metallic layer (14), and subjecting the first and the second metallic layer thus obtained to alloying treatment. The present invention provides favorable ohmic contacts by effecting the alloying treatment at a relatively low temperature of 350 DEG C or even lower.
Abstract:
PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting element having a high reflection factor and excellent electrical contact of a light reflection layer and a semiconductor layer. SOLUTION: The semiconductor layer 20, an underlayer 30, and the light reflection layer 31 are laminated in this order. The semiconductor layer 20 is composed by laminating a buffer layer 21, a GaN layer 22, an n-type contact layer 23, an n-type cladding layer 24, an active layer 25, a p-type cladding layer 26, and a p-type contact layer 27 in this order. The underlayer 30 is formed on the surface of the p-type contact layer 27, Ag (silver) is added to a transition metal, and the underlayer 30 has a thickness of 1 nm or more and 10 nm or less. The light reflection layer 31 is formed on the surface of the underlayer 30, and a prescribed substance is added to Ag. COPYRIGHT: (C)2007,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a method of manufacturing a nitride compound semiconductor device which employs a layer that can be subjected to wet etching as the etch stopper layer to control the structure with high accuracy in a crystal growth stage. SOLUTION: An n-type contact layer 11, an n-type clad layer 12, an active layer 13, and a p-type first clad layer 14A are formed on a substrate 10, and then an etch stopper layer 19 is formed on the p-type first clad layer 14A. The etch stopper layer 19 can be etched with a strong acid or a strong alkali. The layers (a p-type first clad layer 14B and a p-type contact layer 15) above the etch stopper layer 19 are subjected to etching, and then the etch stopper layer 19 is processed by wet etching to form a ridge 16. The p-type first clad layer 14A can be made uniform in thickness without affected by dry etching. COPYRIGHT: (C)2005,JPO&NCIPI
Abstract:
PROBLEM TO BE SOLVED: To provide a semiconductor light emitting device which is superior in characteristics such as light emission characteristics and high in reliability and has a long service life and a semiconductor device which is superior in characteristics and reliability and has a long service life. SOLUTION: Second regions B having second average dislocation density higher than a first region A which is formed of crystal having a first average dislocation density are regularly arranged in the first region A on a nitride III-V compound semiconductor substrate 1. When a semiconductor light emitting device or a semiconductor device is manufactured by the used of the above nitride III-V compound semiconductor substrate 1, the light emitting region of the semiconductor light emitting device or the active region of the semiconductor device is formed so as to avoid the second regions B.
Abstract:
PROBLEM TO BE SOLVED: To provide a nitride semiconductor laser element having a low operating voltage and good stability of the transverse mode. SOLUTION: The semiconductor laser element 10 has a structure composed of first contact layer 14, a first clad layer 16, an active layer 20, a second clad layer 24, a second contact layer 26, and a second electrode 30 laminated one above another. The second clad layer 24 is composed of an upper and lower layers 24A, 24B; the first clad layer 14, the active layer 20 and the lower layer 24A of the second clad layer have mesa structures; the upper layer 24B of the second clad layer and the second contact layer 26 have ridge structures; an insulation layer 40 is formed on a part of the lower layer 24A of the second clad layer corresponding to the top face of the mesa structure, so as to cover at least part of both sides of the upper layer 24B of the second clad layer; and a metal layer 42 having substantially the same width as that of the mesa structure is formed from the top face of the insulation layer 40 to the top face of the second electrode 30.