# US 2014/0196660 A1 · Nitride semiconductor crystal producing method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0196660 A1 - Document ID: US20140196660A1 - Status: Published application - Kind: A1 - Application number: 14/163,967 - Filed: 2014-01-24 - Published: 2014-07-17 - Earliest claimed: 2011-09-12 - Assignees: Hitachi Metals, Ltd. - Applicants: Hitachi Metals, Ltd. - Inventors: Hajime FUJIKURA; Taichiroo KONNO; Yuichi OSHIMA - Web page: https://patentgrep.com/patent/US20140196660A1 ## CPC - C30B 25/02: Epitaxial-layer growth - C30B 25/14: Feed and outlet means for the gases; Modifying the flow of the reactive gases - C30B 25/16: Controlling or regulating (controlling or regulating in general G05) - C30B 25/165: {the flow of the reactive gases} - C30B 29/406: {Gallium nitride} - H10D 62/8503: {Nitride Group III-V materials, e.g. AlN or GaN} - C30B: SINGLE-CRYSTAL GROWTH (by using ultra-high pressure, e.g. for the formation of diamonds, B01J3/06); UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL (zone-refining of metals or alloys C22B); PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (casting of metals, casting of other substances by the same processes or devices B22D; working of plastics B29; modifying the physical structure of metals or alloys C21D, C22F); SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE (for producing semiconductor devices or parts thereof H10); APPARATUS THEREFOR - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES ## Abstract A nitride semiconductor crystal producing method, includes growing a nitride semiconductor crystal over a seed crystal substrate, while applying an etching action to an outer end of the seed crystal substrate during the growing of the nitride semiconductor crystal. ## Claims ### Claim 1 A nitride semiconductor crystal producing method, comprising: growing a nitride semiconductor crystal over a seed crystal substrate, while applying an etching action to an outer end of the seed crystal substrate during the growing of the nitride semiconductor crystal. ### Claim 2 (depends on 1) The nitride semiconductor crystal producing method according to claim 1, further comprising: installing the seed crystal substrate in a container with an inner surface and a sidewall for surrounding an outer side of the seed crystal substrate, wherein an environment adjacent to a portion of the inner surface of the container, which is not contacted with the seed crystal substrate at growth initiation, is an environment to apply an etching action during the nitride semiconductor crystal growing, so that the nitride semiconductor crystal is grown in no contact with the portion of the inner surface of the container throughout an entire period of crystal growth, and in a cross-sectional shape similar to an inner cross-sectional shape of the container. ### Claim 3 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein the inner surface of the container, which is not contacted with the nitride semiconductor crystal, includes a side surface of the sidewall. ### Claim 4 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein the inner surface of the container, which is not contacted with the nitride semiconductor crystal, includes a surface on a side in which the seed crystal substrate is installed. ### Claim 5 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein the environment adjacent to the portion, of the inner surface of the container, which is not contacted with the nitride semiconductor crystal, is an environment in which the etching action weakens with distance from a side surface of the sidewall. ### Claim 6 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein the nitride semiconductor crystal is grown in an environment of coexistence of growth and etching, and the etching action is strengthened by diluting a growing raw material adjacent to the portion of the inner surface of the container, which is not contacted with the nitride semiconductor crystal. ### Claim 7 (depends on 6) The nitride semiconductor crystal producing method according to claim 6, wherein the growing raw material is diluted by feeding an inert gas containing nitrogen, argon or helium. ### Claim 8 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein the etching action is applied by feeding an etching gas or liquid adjacent to the portion of the inner surface of the container, which is not contacted with the nitride semiconductor crystal. ### Claim 9 (depends on 8) The nitride semiconductor crystal producing method according to claim 8, wherein the etching gas contains at least any one of hydrogen, chlorine, and hydrogen chloride. ### Claim 10 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein the nitride semiconductor crystal is grown by feeding a substance for producing an etching species through a catalytic action, and at least a portion of the inner surface of the container, which is not contacted with the nitride semiconductor crystal, comprises a catalyst having the catalytic action, to thereby develop the etching action. ### Claim 11 (depends on 10) The nitride semiconductor crystal producing method according to claim 10, wherein the substance for producing the etching species through the catalytic action is a hydrogen gas. ### Claim 12 (depends on 10) The nitride semiconductor crystal producing method according to claim 10, wherein the catalyst having the catalytic action is a metal or a metal nitride. ### Claim 13 (depends on 12) The nitride semiconductor crystal producing method according to claim 12, wherein the metal is any of Ti, Zr, Nb, Ta, Cr, W, Mo, or Ni. ### Claim 14 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein a distance between the etching action-producing inner surface of the container, which is not contacted with the nitride semiconductor crystal, and the nitride semiconductor crystal, ranges from 1 to 10 mm, for a period from crystal growth initiation until termination. ### Claim 15 (depends on 2) The nitride semiconductor crystal producing method according to claim 2, wherein an angle between a side surface of the sidewall and a placement surface of the container on which the seed crystal substrate is placed ranges greater than 90 degrees and not greater than 135 degrees, so that the inner cross section of the container is shaped to expand toward its opening side, and the nitride semiconductor crystal is grown having a nitrogen face as a growth face, while expanding its diameter.