摘要:
A light emitting device using a group III nitride group compound semiconductor is disclosed. The device includes a substrate, a group III nitride group compound semiconductor layer, and a rectangular parallelepiped stack Rd which is formed by etching multiple group III nitride group compound semiconductor layers laminated on the group III nitride group compound semiconductor layer. The group III nitride group compound semiconductor layer comprises regions, which have many defects and less defects, respectively, and are formed in a striped pattern. Each of the boundaries between the regions with less defects and more defects or a plane which includes a longitudinal edge of the buffer layer is vertical to the substrate and parallel to a longitudinal plane of the rectangular parallelepiped stack Rd. The boundaries and two stack facets Mrr of the rectangular parallelepiped stack Rd are parallel to each other.
摘要:
A semiconductor laser 101 comprises a sapphire substrate 1, an AlN buffer layer 2, Si-doped GaN n-layer 3, Si-doped Al0.1Ga0.9N n-cladding layer 4, Si-doped GaN n-guide layer 5, an active layer 6 having multiple quantum well (MQW) structure in which about 35 Å in thickness of GaN barrier layer 62 and about 35 Å in thickness of Ga0.95In0.05N well layer 61 are laminated alternately, Mg-doped GaN p-guide layer 7, Mg-doped Al0.1Ga0.9N p-cladding layer 8, and Mg-doped GaN p-contact layer 9 are formed successively thereon. A ridged hole injection part B which contacts to a ridged resonator part A is formed to have the same width as the width w of an Ni electrode 10. Holes transmitted from the Ni electrode 10 are injected to the active layer 6 with high current density, and electric current threshold for laser oscillation can be decreased. Electric current threshold can be improved more effectively by forming also the p-guide layer 7 to have the same width as the width w of the Ni electrode 10.
摘要翻译:半导体激光器101包括蓝宝石衬底1,AlN缓冲层2,掺杂Si的GaN n层3,掺杂Si的Al 0.1 Ga 0.9 N n包层4,掺杂Si的GaN n引导层5, 具有多个量子阱(MQW)结构的有源层6,其中厚度约为35的GaN阻挡层62和约35厚度的Ga0.95In0.05N阱层61交替层叠,掺杂Mg的GaN p引导层 如图7所示,依次形成Mg掺杂的Al 0.1 Ga 0.9 N p包覆层8和Mg掺杂的GaN p接触层9。 与脊状谐振器部件A接触的脊状空穴注入部分B形成为具有与Ni电极10的宽度w相同的宽度。从Ni电极10传输的孔以高电流密度注入到有源层6中, 可以降低激光振荡的电流阈值。 也可以通过将p导向层7形成为具有与Ni电极10的宽度w相同的宽度来更有效地提高电流阈值。
摘要:
A first Group III nitride compound semiconductor layer 31 is etched, to thereby form an island-like structure such as a dot-like, stripe-shaped, or grid-like structure, so as to provide a trench/post. Thus, a second Group III nitride compound layer 32 can be epitaxially grown, vertically and laterally, from a top surface of the post and a sidewall/sidewalls of the trench serving as a nucleus for epitaxial growth, to thereby bury the trench and also grow the layer in the vertical direction. In this case, propagation of threading dislocations contained in the first Group III nitride compound semiconductor layer 31 can be prevented in the upper portion of the second Group III nitride compound semiconductor 32 that is formed through lateral epitaxial growth. As a result, a region having less threading dislocations is formed at the buried trench.
摘要:
The present invention provides a Group III nitride compound semiconductor with suppressed generation of threading dislocations. A GaN layer 31 is subjected to etching, so as to form an island-like structure having a shape of, for example, dot, stripe, or grid, thereby providing a trench/mesa structure, and a mask 4 is formed at the bottom of the trench such that the upper surface of the mask 4 is positioned below the top surface of the GaN layer 31. A GaN layer 32 is lateral-epitaxially grown with the top surface 31a of the mesa and sidewalls 31b of the trench serving as nuclei, to thereby bury the trench, and then epitaxial growth is effected in the vertical direction. In the upper region of the GaN layer 32 formed above the mask 4 through lateral epitaxial growth, propagation of threading dislocations contained in the GaN layer 31 can be prevented.
摘要:
The present invention provides a Group III nitride compound semiconductor with suppressed generation of threading dislocations.A GaN layer 31 is subjected to etching, so as to form an island-like structure having a shape of, for example, dot, stripe, or grid, thereby providing a trench/mesa structure, and a mask 4 is formed at the bottom of the trench such that the upper surface of the mask 4 is positioned below the top surface of the GaN layer 31. A GaN layer 32 is lateral-epitaxially grown with the top surface 31a of the mesa and sidewalls 31b of the trench serving as nuclei, to thereby bury the trench, and then epitaxial growth is effected in the vertical direction. In the upper region of the GaN layer 32 formed above the mask 4 through lateral epitaxial growth, propagation of threading dislocations contained in the GaN layer 31 can be prevented.
摘要:
A first Group III nitride compound semiconductor layer 31 is etched, to thereby form an island-like structure such as a dot-like, stripe-shaped, or grid-like structure, so as to provide a trench/post. Thus, a second Group III nitride compound layer 32 can be epitaxially grown, vertically and laterally, from a top surface of the post and a sidewall/sidewalls of the trench serving as a nucleus for epitaxial growth, to thereby bury the trench and also grow the layer in the vertical direction. In this case, propagation of threading dislocations contained in the first Group III nitride compound semiconductor layer 31 can be prevented in the upper portion of the second Group III nitride compound semiconductor 32 that is formed through lateral epitaxial growth. As a result, a region having less threading dislocations is formed at the buried trench.
摘要:
A first Group III nitride compound semiconductor layer 31 is etched, to thereby form an island-like structure such as a dot-like, stripe-shaped, or grid-like structure, so as to provide a trench/mesa such that layer different from the first Group III nitride compound semiconductor layer 31 is exposed at the bottom portion of the trench. Thus, a second Group III nitride compound layer 32 can be epitaxially grown, laterally, with a top surface of the mesa and a sidewall/sidewalls of the trench serving as a nucleus, to thereby bury the trench and also grow the layer in the vertical direction. In this case, propagation of threading dislocations contained in the first Group III nitride compound semiconductor layer 31 can be prevented in the upper portion of the second Group III nitride compound semiconductor 32 that is formed through lateral epitaxial growth. Etching may be performed until a cavity portion is provided in the substrate. The layer serving as a nucleus of ELO may be doped with indium (In) having an atomic radius greater than that of gallium (Ga) serving as a predominant element. The first semiconductor layer may be a multi-component layer containing a plurality of numbers of repetitions of a unit of a buffer layer and a single-crystal layer.
摘要:
The present invention provides a Group III nitride compound semiconductor with suppressed generation of threading dislocations. A GaN layer 31 is subjected to etching, so as to form an island-like structure having a shape of, for example, dot, strip, or grid, thereby providing a trench/mesa structure, and a mask 4 is formed at the bottom of the trench such that the upper surface of the mask 4 is positioned below the top surface of the GaN layer 31. A GaN layer 32 is lateral-epitaxially grown with the top surface 31a of the mesa and sidewalls 31b of the trench serving as nuclei, to thereby bury the trench, and then epitaxial growth is effected in the vertical direction. In the upper region of the GaN layer 32 formed above the mask 4 through lateral epitaxial growth, propagation of threading dislocations contained in the GaN layer is 31 can be prevented.
摘要:
By using a mask 4, a first Group III nitride compound semiconductor layer 31 is etched, to thereby form an island-like structure such as a dot-like, striped-shaped, or grid-like structure, so as to provide a trench/post. Thus, without removing the mask 4 formed on a top surface of the upper layer of the post, a second Group III nitride compound layer 32 can be epitaxially grown, vertically and laterally, with a sidewall/sidewalls of the trench serving as a nucleus, to thereby bury the trench and also grow the layer in the vertical direction. The second Group III nitride compound layer 32 does not grow epitaxially on the mask 4. In this case, propagation of threading dislocations contained in the first Group III nitride compound semiconductor layer 31 can be prevented in the upper portion of the second Group III nitride compound semiconductor 32 that is formed through lateral epitaxial growth and a region having less threading dislocations can be formed in the buried portion of the trench.
摘要:
When a substrate layer (desired semiconductor crystal) made of a group III nitride compound is grown on a base substrate comprising a lot of projection parts, a cavity in which a semiconductor crystal is not deposited may be formed between each projection part although it depends on conditions such as the size of each projection part, arranging interval between each projection part and crystal growth. So when the thickness of the substrate layer is sufficiently larger compared with the height of the projection part, inner stress or outer stress become easier to act intensively to the projection part. As a result, such stress especially functions as shearing stress toward the projection part. When the shearing stress becomes larger, the projection part is ruptured. So utilizing the shearing stress enables to separate the base substrate and the substrate layer easily. The larger the cavities are formed, the more stress tends to concentrate to the projection parts, to thereby enable to separate the base substrate and the substrate layer more securely.