Mitsubishi Chemical Corporation

Yuuki Enatsu

Kenji Iso

Satoru Nagao

Kenji Fujito

Shuichi Kubo

Hirotaka Ikeda

Tatsuya Takahashi

Tae Mochizuki

Hiromitsu Kimura

Kenji Shimoyama

Yuya Saito

Provided is a GaN substrate wafer with an improved productivity, which can be preferably used in the production of a nitride semiconductor device having a horizontal device structure. The GaN substrate wafer is a (0001)-oriented GaN substrate wafer that includes a first region arranged on an N-polar side and a second region, which is arranged on a Ga-polar side and has a minimum thickness, via a regrowth interface therebetween. In this GaN substrate wafer, the second region has a minimum thickness of not less than 20 μm, and at least a portion of the second region has a total compensating impurity concentration of 1×10atoms/cmor higher.

GaN substrate wafer and production method for same

Provided is an n-type GaN crystal, in which a donor impurity contained at the highest concentration is Ge, and which has a room-temperature resistivity of lower than 0.03 Ω·cm and a (004) XRD rocking curve FWHM of less than 20 arcsec. The n-type GaN crystal has two main surfaces, each having an area of 3 cmor larger. One of the two main surfaces can have a Ga polarity and can be inclined at an angle of 0° to 10° with respect to a (0001) crystal plane. Further, the n-type GaN crystal can have a diameter of 20 mm or larger.

n-Type GaN crystal, GaN wafer, and GaN crystal, GaN wafer and nitride semiconductor device production method

Provided are: a GaN substrate wafer having a crystallinity suitable as a substrate for a semiconductor device as well as an improved productivity; and a method of producing the same. The GaN substrate wafer is a (0001)-oriented GaN substrate wafer that includes a first region arranged on an N-polar side and a second region arranged on a Ga-polar side via a regrowth interface therebetween. In this GaN substrate wafer, the second region has a minimum thickness of not less than 20 μm, the concentration of at least one element selected from Li, Na, K, F, Cl, Br, and I in the first region is 1×10atoms/cmor higher, and the second region satisfies one or more conditions selected from the following (a) to (c): (a) the Si concentration is 5×10atoms/cmor higher; (b) the O concentration is 3×10atoms/cmor lower; and (c) the H concentration is 1×10atoms/cmor lower.

GaN substrate wafer and method for manufacturing same

Provided is an n-type GaN crystal, in which a donor impurity contained at the highest concentration is Ge, and which has a room-temperature resistivity of lower than 0.03 Ω·cm and a (004) XRD rocking curve FWHM of less than 20 arcsec. The n-type GaN crystal has two main surfaces, each having an area of 2 cmor larger. One of the two main surfaces can have a Ga polarity and can be inclined at an angle of 0° to 10° with respect to a (0001) crystal plane. Further, the n-type GaN crystal can have a diameter of 20 mm or larger.

N-type GaN crystal, GaN wafer, and GaN crystal, GaN wafer and nitride semiconductor device production method

A periodic table Group 13 metal nitride crystals grown with a non-polar or semi-polar principal surface have numerous stacking faults. The purpose of the present invention is to provide a period table Group 13 metal nitride crystal wherein the occurrence of stacking faults of this kind are suppressed. The present invention achieves the foregoing by a periodic table Group 13 metal nitride crystal being characterized in that, in a Qx direction intensity profile that includes a maximum intensity and is derived from an isointensity contour plot obtained by x-ray reciprocal lattice mapping of (100) plane of the periodic table Group 13 metal nitride crystal, a Qx width at 1/300th of peak intensity is 6&#xd7;10rlu or less.

Periodic table group 13 metal nitride crystals and method for manufacturing periodic table group 13 metal nitride crystals

Provides is a C-plane GaN substrate which, although formed from a GaN crystal grown so that surface pits are generated, is free from any inversion domain, and moreover, has a low spiral dislocation density in a gallium polar surface. Provides is a C-plane GaN substrate wherein: the substrate comprises a plurality of facet growth areas each having a closed ring outline-shape on a gallium polar surface; the spiral dislocation density is less than 1&#xd7;10cmanywhere on the gallium polar surface; and the substrate is free from any inversion domain. The C-plane GaN substrate may comprise a high dislocation density part having a dislocation density of more than 1&#xd7;10cmand a low dislocation density part having a dislocation density of less than 1&#xd7;10cmon the gallium polar surface.

C-plane GaN substrate

A C-plane GaN substrate only mildly restricts the shape and dimension of a nitride semiconductor device formed on the substrate. The variation of an off-angle on the main surface of the substrate is suppressed. In the C-plane GaN substrate: the substrate comprises a plurality of facet growth areas each having a closed ring outline-shape on the main surface; the number density of the facet growth area accompanied by a core among the plurality of facet growth areas is less than 5 cmon the main surface; and, when any circular area of 4 cm diameter is selected from an area which is on the main surface and is distant by 5 mm or more from the outer peripheral edge of the substrate, the variation widths of an a-axis direction component and an m-axis direction component of an off-angle within the circular area is each 0.25 degrees or less.

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Ushiku, Japan

Yuuki Enatsu