摘要:
The present invention provides a method for producing a semiconductor substrate, the method including reacting nitrogen (N) with gallium (Ga), aluminum (Al), or indium (In), which are group III elements, in a flux mixture containing a plurality of metal elements selected from among alkali metals and alkaline earth metals, to thereby grow a group III nitride based compound semiconductor crystal. The group III nitride based compound semiconductor crystal is grown while the flux mixture and the group III element are mixed under stirring. At least a portion of a base substrate on which the group III nitride based compound semiconductor crystal is grown is formed of a flux-soluble material, and the flux-soluble material is dissolved in the flux mixture, at a temperature near the growth temperature of the group III nitride based compound semiconductor crystal, during the course of growth of the semiconductor crystal.
摘要:
To provide a semiconductor substrate of high quality suitable for fabricating an electronic device or an optical device. The present invention provides a method for producing a semiconductor substrate for an electronic device or an optical device, the method including reacting nitrogen (N) with gallium (Ga), aluminum (Al), or indium (In), which are group III elements, in a flux mixture containing a plurality of metal elements selected from among alkali metals and alkaline earth metals, to thereby grow a group III nitride based compound semiconductor crystal. The group III nitride based compound semiconductor crystal is grown while the flux mixture and the group III element are mixed under stirring. At least a portion of a base substrate on which the group III nitride based compound semiconductor crystal is grown is formed of a flux-soluble material, and the flux-soluble material is dissolved in the flux mixture, at a temperature near the growth temperature of the group III nitride based compound semiconductor crystal, during the course of growth of the semiconductor crystal or after completion of growth of the semiconductor crystal.
摘要:
The present invention provides a method for producing a semiconductor substrate, the method including reacting nitrogen (N) with gallium (Ga), aluminum (Al), or indium (In), which are group III elements, in a flux mixture containing a plurality of metal elements selected from among alkali metals and alkaline earth metals, to thereby grow a group III nitride based compound semiconductor crystal. The group III nitride based compound semiconductor crystal is grown while the flux mixture and the group III element are mixed under stirring. At least a portion of a base substrate on which the group III nitride based compound semiconductor crystal is grown is formed of a flux-soluble material, and the flux-soluble material is dissolved in the flux mixture, at a temperature near the growth temperature of the group III nitride based compound semiconductor crystal, during the course of growth of the semiconductor crystal.
摘要:
An object of the invention is to carry out the flux method with improved work efficiency while maintaining the purity of flux at high level and saving flux material cost. The sodium-purifying apparatus includes a sodium-holding-and-management apparatus for maintaining purified sodium (Na) in a liquid state. Liquid sodium is supplied into a sodium-holding-and-management apparatus through a liquid-sodium supply piping maintained at 100° C. to 200° C. The sodium-holding-and-management apparatus further has an argon-gas-purifying apparatus for controlling the condition of argon (Ar) gas that fills the internal space thereof. Thus, by opening and closing a faucet at desired timing, purified liquid sodium (Na) supplied from the sodium-purifying apparatus can be introduced into a crucible as appropriate via the liquid-sodium supply piping, the sodium-holding-and-management apparatus, and the piping.
摘要:
The present invention provides a method for producing a Group III nitride compound semiconductor crystal, the semiconductor crystal being grown through the flux method employing a flux. At least a portion of a substrate on which the semiconductor crystal is to be grown is formed of a flux-soluble material. While the semiconductor crystal is grown on a surface of the substrate, the flux-soluble material is dissolved in the flux from a surface of the substrate that is opposite the surface on which the semiconductor crystal is grown. Alternatively, after the semiconductor crystal has been grown on a surface of the substrate, the flux-soluble material is dissolved in the flux from a surface of the substrate that is opposite the surface on which the semiconductor crystal has been grown. The flux-soluble material is formed of silicon. Alternatively, the flux-soluble material or the substrate is formed of a Group III nitride compound semiconductor having a dislocation density higher than that of the semiconductor crystal to be grown.
摘要:
An object of the invention is to carry out the flux method with improved work efficiency while maintaining the purity of flux at high level and saving flux material cost. The sodium-purifying apparatus includes a sodium-holding-and-management apparatus for maintaining purified sodium (Na) in a liquid state. Liquid sodium is supplied into a sodium-holding-and-management apparatus through a liquid-sodium supply piping maintained at 100° C. to 200° C. The sodium-holding-and-management apparatus further has an argon-gas-purifying apparatus for controlling the condition of argon (Ar) gas that fills the internal space thereof. Thus, by opening and closing a faucet at desired timing, purified liquid sodium (Na) supplied from the sodium-purifying apparatus can be introduced into a crucible as appropriate via the liquid-sodium supply piping, the sodium-holding-and-management apparatus, and the piping.
摘要:
The present invention provides a method for producing a Group III nitride compound semiconductor crystal, the semiconductor crystal being grown through the flux method employing a flux. At least a portion of a substrate on which the semiconductor crystal is to be grown is formed of a flux-soluble material. While the semiconductor crystal is grown on a surface of the substrate, the flux-soluble material is dissolved in the flux from a surface of the substrate that is opposite the surface on which the semiconductor crystal is grown. Alternatively, after the semiconductor crystal has been grown on a surface of the substrate, the flux-soluble material is dissolved in the flux from a surface of the substrate that is opposite the surface on which the semiconductor crystal has been grown. The flux-soluble material is formed of silicon. Alternatively, the flux-soluble material or the substrate is formed of a Group III nitride compound semiconductor having a dislocation density higher than that of the semiconductor crystal to be grown.
摘要:
In the production of GaN through the flux method, deposition of miscellaneous crystals on the nitrogen-face of a GaN self-standing substrate and waste of raw materials are prevented. Four arrangements of crucibles and a GaN self-standing substrate are exemplified. In FIG. 1A, a nitrogen-face of a self-standing substrate comes into close contact with a sloped flat inner wall of a crucible. In FIG. 1B, a nitrogen-face of a self-standing substrate comes into close contact with a horizontally facing flat inner wall of a crucible, and the substrate is fixed by means of a jig. In FIG. 1C, a jig is provided on a flat bottom of a crucible, and two GaN self-standing substrates are fixed by means of the jig so that the nitrogen-faces of the substrates come into close contact with each other. In FIG. 1D, a jig is provided on a flat bottom of a crucible, and a GaN self-standing substrate is fixed on the jig so that the nitrogen-face of the substrate is covered with the jig. A flux mixture of molten gallium and sodium is charged into each crucible, and a GaN single crystal is grown on a gallium-face under pressurized nitrogen.
摘要:
Objects of the invention are to further enhance crystallinity and crystallinity uniformity of a semiconductor crystal produced through the flux method, and to effectively enhance the production yield of the semiconductor crystal. The c-axis of a seed crystal including a GaN single-crystal layer is aligned in a horizontal direction (y-axis direction), one a-axis of the seed crystal is aligned in the vertical direction, and one m-axis is aligned in the x-axis direction. Thus, three contact points at which a supporting tool contacts the seed crystal are present on m-plane. The supporting tool has two supporting members, which extend in the vertical direction. One supporting member has an end part, which is inclined at 30° with respect to the horizontal plane α. The reasons for supporting a seed crystal at m-plane thereof are that m-plane exhibits a crystal growth rate, which is lower than that of a-plane, and that desired crystal growth on c-plane is not inhibited. Actually, a plurality of seed crystals and supporting tools are periodically placed along the y-axis direction.
摘要:
Objects of the invention are to further enhance crystallinity and crystallinity uniformity of a semiconductor crystal produced through the flux method, and to effectively enhance the production yield of the semiconductor crystal. The c-axis of a seed crystal including a GaN single-crystal layer is aligned in a horizontal direction (y-axis direction), one a-axis of the seed crystal is aligned in the vertical direction, and one m-axis is aligned in the x-axis direction. Thus, three contact points at which a supporting tool contacts the seed crystal are present on m-plane. The supporting tool has two supporting members, which extend in the vertical direction. One supporting member has an end part, which is inclined at 30° with respect to the horizontal plane α. The reasons for supporting a seed crystal at m-plane thereof are that m-plane exhibits a crystal growth rate, which is lower than that of a-plane, and that desired crystal growth on c-plane is not inhibited. Actually, a plurality of seed crystals and supporting tools are periodically placed along the y-axis direction.