Ngk Insulators, Inc.

Osaka University

Mikiya Ichimura

Mitsuhiro Tanaka

Makoto Miyoshi

Yoshitaka Kuraoka

Sota Maehara

Shigeaki Sumiya

Katsuhiro Imai

Takayuki Hirao

Tomohiko Sugiyama

Takashi Yoshino

Masahiro Sakai

Takanao Shimodaira

Hirokazu Nakanishi

Makoto Iwai

Fumio Kawamura

Takatomo Sasaki

Jun Yoshikawa

Yusuke Mori

Yasuo Kitaoka

Masahiko Namerikawa

Takahiro Tomita

Shigeharu Hashimoto

Chikashi Ihara

A layer of a crystal of a group 13 nitride selected from gallium nitride, aluminum nitride, indium nitride and the mixed crystals thereof has an upper surface and a bottom surface. The upper surface of a crystal layer of the group 13 nitride includes a linear high-luminance light-emitting part and a low-luminance light-emitting region adjacent to the high-luminance light-emitting part, observed by cathode luminescence. The high-luminance light-emitting part includes a portion extending along an m-plane of the crystal of the group 13 nitride. The crystal of the nitride of the group 13 element contains oxygen atoms in a content of 1&#xd7;10atom/cmor less, silicon atoms, manganese atoms, carbon atoms, magnesium atoms and calcium atoms in contents of 1&#xd7;10atom/cmor less, chromium atoms in a content of 1&#xd7;10atom/cmor less and chlorine atoms in a content of 1&#xd7;10atom/cmor less.

Group 13 element nitride layer, free-standing substrate and functional element

A layer of a crystal of a group 13 nitride selected from gallium nitride, aluminum nitride, indium nitride and the mixed crystals thereof has an upper surface and a bottom surface. The upper surface includes a linear high-luminance light-emitting part and a low-luminance light-emitting region adjacent to the high-luminance light-emitting part. The high-luminance light-emitting part includes a portion extending along an m-plane of the crystal of the group 13 nitride. A normal line to the upper surface has an off-angle of 2.0&#xb0; or less with respect to &#x3c;0001&#x3e; direction of the crystal of the nitride of the group 13 element.

A layer of a crystal of a nitride of a group 13 element selected from gallium nitride, aluminum nitride, indium nitride and the mixed crystals thereof includes an upper surface and a bottom surface. The upper surface includes a linear high-luminance light-emitting part and a low-luminance light-emitting region adjacent to the high-luminance light-emitting part, and the high-luminance light-emitting part has a portion extending along an m-plane of the crystal of the nitride of the group 13 element, when the upper surface is observed by cathode luminescence. The upper surface has an arithmetic average roughness Ra of 0.05 nm or more and 1.0 nm or less.

A crystal of a group 13 nitride has an upper surface and lower surface and is composed of a crystal of a group 13 nitride selected from gallium nitride, aluminum nitride, indium nitride or the mixed crystals thereof. When the upper surface of the layer of the crystal of the group 13 nitride is observed by cathode luminescence, the upper surface includes a linear high-luminance light-emitting part and a low-luminance light-emitting region adjacent to the high-luminance light-emitting part. A half value width of reflection at the (0002) plane of a X-ray rocking curve on the upper surface is 3000 seconds or less and 20 seconds or more.

A layer of a crystal of a groupnitride selected from gallium nitride, aluminum nitride, indium nitride and the mixed crystals thereof has an upper surface and a bottom surface. The upper surface of the crystal layer of the groupnitride includes a linear high-luminance light-emitting part and a low-luminance light-emitting region adjacent to the high-luminance light-emitting part, observed by cathode luminescence. The high-luminance light-emitting part includes a portion extending along an m-plane of the crystal of the groupnitride.

A free-standing substrate of a polycrystalline nitride of a group 13 element contains a plurality of monocrystalline particles having a particular crystal orientation in approximately a normal direction. The polycrystalline nitride of the group 13 element is composed of gallium nitride, aluminum nitride, indium nitride or a mixed crystal thereof. The free-standing substrate has a top surface and bottom surface. The free-standing substrate contains at least one of zinc and calcium. A root mean square roughness Rms at the top surface is 3.0 nm or less.

Free-standing substrate comprising polycrystalline group 13 element nitride and light-emitting element using same

An epitaxial substrate for semiconductor elements suppresses leakage current and has a high breakdown voltage. The epitaxial substrate for semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN doped with Zn; a buffer layer formed of a group 13 nitride adjacent to the free-standing substrate; a channel layer formed of a group 13 nitride adjacent to the buffer layer; and a barrier layer formed of a group 13 nitride on an opposite side of the buffer layer with the channel layer therebetween, wherein part of a first region consisting of the free-standing substrate and the buffer layer is a second region containing Si at a concentration of 1&#xd7;10cmor more, and a minimum value of a concentration of Zn in the second region is 1&#xd7;10cm.

Epitaxial substrate for semiconductor elements, semiconductor element, and manufacturing method for epitaxial substrates for semiconductor elements

A free-standing substrate of a polycrystalline nitride of a group 13 element is composed of a plurality of monocrystalline particles having a particular crystal orientation in approximately a normal direction. The free-standing substrate has a top surface and a bottom surface. The polycrystalline nitride of the group 13 element is gallium nitride, aluminum nitride, indium nitride or a mixed crystal thereof and contains zinc at a concentration of 1&#xd7;10atoms/cmor more and 1&#xd7;10atoms/cmor less.

An epitaxial substrate for semiconductor elements is provided which suppresses the occurrence of current collapse. The epitaxial substrate for the semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN doped with Zn; a buffer layer adjacent to the free-standing substrate; a channel layer adjacent to the buffer layer; and a barrier layer provided on an opposite side of the buffer layer with the channel layer therebetween, wherein the buffer layer is a diffusion suppressing layer formed of AlGaN (0.7&#x2264;p&#x2264;1) and suppresses diffusion of Zn from the free-standing substrate into the channel layer.

Provided is an epitaxial substrate for semiconductor elements which suppresses an occurrence of current collapse. The epitaxial substrate for the semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN being doped with Zn; a buffer layer being adjacent to the free-standing substrate; a channel layer being adjacent to the buffer layer; and a barrier layer being provided on an opposite side of the buffer layer with the channel layer therebetween, wherein the buffer layer is a diffusion suppressing layer formed of Al-doped GaN and suppresses diffusion of Zn from the free-standing substrate into the channel layer.

An epitaxial substrate for semiconductor elements which suppresses the occurrence of current collapse. The epitaxial substrate for the semiconductor elements includes: a semi-insulating free-standing substrate formed of GaN doped with Zn; a buffer layer adjacent to the free-standing substrate; a channel layer adjacent to the buffer layer; and a barrier layer provided on an opposite side of the buffer layer with the channel layer provided therebetween, wherein the buffer layer is a diffusion suppressing layer that suppresses the diffusion of Zn from the free-standing substrate into the channel layer.

Provided are a group 13 nitride composite substrate allowing for the production of a semiconductor device suitable for high-frequency applications while including a conductive GaN substrate, and a semiconductor device produced using this substrate. The group 13 nitride composite substrate includes a base material of an n-conductivity type formed of GaN, a base layer located on the base material, being a group 13 nitride layer having a resistivity of 1&#xd7;10&#x3a9;&#xb7;cm or more, a channel layer located on the base layer, being a GaN layer having a total impurity density of 1&#xd7;10/cmor less, and a barrier layer that is located on the channel layer and is formed of a group 13 nitride having a composition AlInGaN (0&#x2264;x&#x2264;1, 0&#x2264;y&#x2264;1).

Group 13 nitride composite substrate semiconductor device, and method for manufacturing group 13 nitride composite substrate

Provided is a group 13 nitride epitaxial substrate with which the HEMT device having superior characteristics can be manufactured. This epitaxial substrate is provided with: a base substrate composed of SiC and having a main surface with a (0001) plane orientation; a nucleation layer formed on one main surface of the base substrate and composed of AlN; an electron transit layer formed on the nucleation layer and composed of a group 13 nitride with the composition AlGaN (0&#x2264;y&#x3c;1); and a barrier layer formed on the electron transit layer and composed of a group 13 nitride with the composition InAlN (0.13&#x2264;z&#x2264;0.23) or AlGaN (0.15&#x2264;w&#x2264;0.35). The (0001) plane of the base substrate has an off angle of 0.1&#xb0; or more and 0.5&#xb0; or less, and an intermediate layer composed of a group 13 nitride with the composition AlGaN (0.01 &#x2264;x&#x2264;0.4) is further provided between the nucleation layer and the electron transit layer.

Epitaxial substrate for semiconductor device and method for manufacturing same

A supporting substrate for a composite substrate comprises a ceramic and has a polished surface for use in bonding. An orientation degree of the ceramic forming the supporting substrate at the polished surface is 50% or higher, and an aspect ratio of each crystal grain included in the supporting substrate is 5.0 or less.

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Ichinomiya, Japan

Mikiya Ichimura