摘要:
A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device 11a includes a group III nitride semiconductor supporting base 13, a GaN based semiconductor region 15, an active layer active layer 17, and a GaN semiconductor region 19. The primary surface 13a of the group III nitride semiconductor supporting base 13 is not any polar plane, and forms a finite angle with a reference plane Sc that is orthogonal to a reference axis Cx extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region 15 is grown on the semipolar primary surface 13a. A GaN based semiconductor layer 21 of the GaN based semiconductor region 15 is, for example, an n-type GaN based semiconductor, and the n-type GaN based semiconductor is doped with silicon. A GaN based semiconductor layer 23 of an oxygen concentration of 5×1016 cm−3 or more provides an active layer 17 with an excellent crystal quality, and the active layer 17 is grown on the primary surface of the GaN based semiconductor layer 23.
摘要:
In step S106, an InXGa1-XN well layer is grown on a semipolar main surface between times t4 and t5 while a temperature in a growth furnace is maintained at temperature TW. In step S107, immediately after completion of the growth of the well layer, the growth of a protective layer covering the main surface of the well layer is initiated at temperature TW. The protective layer is composed of a gallium nitride-based semiconductor with a band gap energy that is higher than that of the well layer and equal to or less than that of a barrier layer. In step S108, the temperature in the furnace is changed from temperatures TW to TB before the barrier layer growth. The barrier layer composed of the gallium nitride-based semiconductor is grown on the protective layer between times t8 and t9 while the temperature in the furnace is maintained at temperature TB.
摘要:
A nitride-based semiconductor light-emitting element LE1 or LD1 has: a gallium nitride substrate 11 having a principal surface 11a which makes an angle α, in the range 40° to 50° or in the range more than 90° to 130°, with the reference plane Sc perpendicular to the reference axis Cx extending in the c axis direction; an n-type gallium nitride-based semiconductor layer 13; a second gallium nitride-based semiconductor layer 17; and a light-emitting layer 15 including a plurality of well layers of InGaN and a plurality of barrier layers 23 of a GaN-based semiconductor, wherein the direction of piezoelectric polarization of the plurality of well layers 21 is the direction from the n-type gallium nitride-based semiconductor layer 13 toward the second gallium nitride-based semiconductor layer 17.
摘要:
Provided is a group-III nitride semiconductor laser device with a laser cavity allowing for a low threshold current, on a semipolar surface of a support base in which the c-axis of a hexagonal group-III nitride is tilted toward the m-axis. First and second fractured faces 27, 29 to form the laser cavity intersect with an m-n plane. The group-III nitride semiconductor laser device 11 has a laser waveguide extending in a direction of an intersecting line between the m-n plane and the semipolar surface 17a. In a laser structure 13, a first surface 13a is opposite to a second surface 13b. The first and second fractured faces 27, 29 extend from an edge 13c of the first surface to an edge 13d of the second surface 13b. The fractured faces are not formed by dry etching and are different from conventionally-employed cleaved facets such as c-planes, m-planes, or a-planes.
摘要:
A nitride semiconductor light emitting device is provided. A core semiconductor region, a first cladding region, and a second cladding region are mounted on a nonpolar primary surface of a support substrate of GaN which is not the polar plane. The core semiconductor region includes an active layer and a carrier block layer. The first cladding region includes an n-type AlGaN cladding layer and an n-type InAlGaN cladding layer. The n-type InAlGaN cladding layer is provided between the n-type AlGaN cladding layer and the active layer. A misfit dislocation density at an interface is larger than that at an interface. The AlGaN cladding layer is lattice-relaxed with respect to the GaN support substrate and the InAlGaN cladding layer is lattice-relaxed with respect to the AlGaN cladding layer.
摘要:
A method of making a semiconductor light-emitting device involves the steps of selecting at least one tilt angle for a primary surface of a substrate to evaluate the direction of piezoelectric polarization in a light-emitting layer, the substrate comprising a group III nitride semiconductor; preparing a substrate having the primary surface, the primary surface having the selected tilt angle, and the primary surface comprising the group III nitride semiconductor; forming a quantum well structure and p- and n-type gallium nitride semiconductor layers for the light-emitting layer at the selected tilt angle to prepare a substrate product; measuring photoluminescence of the substrate product while applying a bias to the substrate product, to determine bias dependence of the photoluminescence; evaluating the direction of the piezoelectric polarization in the light-emitting layer at the selected tilt angle on the primary surface of the substrate by the determined bias dependence; determining which of the primary surface or the back surface of the substrate is to be used, based on the evaluation to select a plane orientation of a growth substrate for making the semiconductor light-emitting device; and forming a semiconductor laminate for the semiconductor light-emitting device on the primary surface of the growth substrate. The tilt angle is defined by the primary surface of the substrate and the (0001) plane of the group III nitride semiconductor. Each of the well layer and the barrier layer of the light-emitting layer extends along a reference plane tilting from a plane perpendicular to a reference axis extending along the c-axis of the group III nitride semiconductor.
摘要:
A method of fabricating a group-III nitride semiconductor laser device includes: preparing a substrate of a hexagonal group-III nitride semiconductor, where the substrate has a semipolar primary surface; forming a substrate product having a laser structure, an anode electrode and a cathode electrode, where the laser structure includes the substrate and a semiconductor region, and where the semiconductor region is formed on the semipolar primary surface; scribing a first surface of the substrate product in part in a direction of the a-axis of the hexagonal group-III nitride semiconductor; and carrying out breakup of the substrate product by press against a second surface of the substrate product, to form another substrate product and a laser bar.
摘要:
A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device includes a group III nitride semiconductor supporting base, a GaN based semiconductor region, an active layer, and a GaN semiconductor region. The primary surface of the group III nitride semiconductor supporting base is not any polar plane, and forms a finite angle with a reference plane that is orthogonal to a reference axis extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region, grown on the semipolar primary surface, includes a semiconductor layer of, for example, an n-type GaN based semiconductor doped with silicon. A GaN based semiconductor layer of an oxygen concentration of 5×1016 cm−3 or more provides an active layer, grown on the primary surface, with an excellent crystal quality.
摘要:
A group III nitride semiconductor device having a gallium nitride based semiconductor film with an excellent surface morphology is provided. A group III nitride optical semiconductor device 11a includes a group III nitride semiconductor supporting base 13, a GaN based semiconductor region 15, an active layer active layer 17, and a GaN semiconductor region 19. The primary surface 13a of the group III nitride semiconductor supporting base 13 is not any polar plane, and forms a finite angle with a reference plane Sc that is orthogonal to a reference axis Cx extending in the direction of a c-axis of the group III nitride semiconductor. The GaN based semiconductor region 15 is grown on the semipolar primary surface 13a. A GaN based semiconductor layer 21 of the GaN based semiconductor region 15 is, for example, an n-type GaN based semiconductor, and the n-type GaN based semiconductor is doped with silicon. A GaN based semiconductor layer 23 of an oxygen concentration of 5×1016 cm−3 or more provides an active layer 17 with an excellent crystal quality, and the active layer 17 is grown on the primary surface of the GaN based semiconductor layer 23.
摘要:
In the method of fabricating a quantum well structure which includes a well layer and a barrier layer, the well layer is grown at a first temperature on a sapphire substrate. The well layer comprises a group III nitride semiconductor which contains indium as a constituent. An intermediate layer is grown on the InGaN well layer while monotonically increasing the sapphire substrate temperature from the first temperature. The group III nitride semiconductor of the intermediate layer has a band gap energy larger than the band gap energy of the InGaN well layer, and a thickness of the intermediate layer is greater than 1 nm and less than 3 nm in thickness. The barrier layer is grown on the intermediate layer at a second temperature higher than the first temperature. The barrier layer comprising a group III nitride semiconductor and the group III nitride semiconductor of the barrier layer has a band gap energy larger than the band gap energy of the well layer.