Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.

Abstract: A crystal manufacturing apparatus for manufacturing a group III nitride crystal includes a crucible that holds a mixed molten liquid including an alkali metal and a group III metal; a reaction vessel accommodating the crucible in the reaction vessel; a heating device that heats the crucible with the reaction vessel; a holding vessel having a lid that is capable of opening and closing, accommodating the reaction vessel and the heating device in the holding vessel; a sealed vessel accommodating the holding vessel in the sealed vessel, having an operating device that enables opening the lid of the holding vessel for supplying source materials into the crucible and taking out a manufactured GaN crystal under a sealed condition, and closing the lid of the holding vessel that is sealed in the sealed vessel, the sealed vessel including an inert gas atmosphere or a nitrogen atmosphere; and a gas supplying device for supplying a nitrogen gas to the mixed molten liquid through each of the vessels.

Abstract: A crystal manufacturing apparatus for manufacturing a group III nitride crystal includes a crucible that holds a mixed molten liquid including an alkali metal and a group III metal; a reaction vessel accommodating the crucible in the reaction vessel; a heating device that heats the crucible with the reaction vessel; a holding vessel having a lid that is capable of opening and closing, accommodating the reaction vessel and the heating device in the holding vessel; a sealed vessel accommodating the holding vessel in the sealed vessel, having an operating device that enables opening the lid of the holding vessel for supplying source materials into the crucible and taking out a manufactured GaN crystal under a sealed condition, and closing the lid of the holding vessel that is sealed in the sealed vessel, the sealed vessel including an inert gas atmosphere or a nitrogen atmosphere; and a gas supplying device for supplying a nitrogen gas to the mixed molten liquid through each of the vessels.

Abstract: In a method of producing a group III nitride crystal in which a melt holding vessel where a melt containing a group III metal and flux is held is accommodated in a reaction vessel and a group III nitride crystal is produced as a substance containing nitrogen is supplied from an outside to the reaction vessel through a pipe, the method includes a step of forming an accumulated part of a liquid in the pipe to thereby temporarily close the pipe before growing the group III nitride crystal in the melt holding vessel.

Abstract: A crystal has a diameter of 1 cm or more and shows a strongest peak in cathode luminescent spectrum at a wavelength of 360 nm in correspondence to a band edge.

Abstract: A positional error detection method forms, on a belt which is transported in a transport direction, positional error detection marks for detecting a positional error between image positions of first and second colors, detects the positional error detection marks on the belt, and computes the positional error based on the detected positional error detection marks. The positional error detection marks include first and second marks which are inclined in mutually opposite directions with respect to the transport direction, and third marks which are perpendicular to the transport direction.

Abstract: A group-III nitride crystal growth method comprises the steps of: a) preparing a mixed molten liquid of an alkaline material and a substance at least containing a group-III metal; b) causing growth of a group-III nitride crystal from the mixed molten liquid prepared in the step a) and a substance at least containing nitrogen; and c) creating a state in which nitrogen can be introduced into the molten liquid prepared by the step a).

Abstract: A group-III nitride crystal growth method comprises the steps of: a) preparing a mixed molten liquid of an alkaline material and a substance at least containing a group-III metal; b) causing growth of a group-III nitride crystal from the mixed molten liquid prepared in the step a) and a substance at least containing nitrogen; and c) creating a state in which nitrogen can be introduced into the molten liquid prepared by the step a).

Abstract: An AM (Amplitude-Modulated) transmitter capable of improving modulation distortion is provided. An adder adds a modulation signal to a pre-set power reference signal. An APC (Automatic Power Control) amplifier compares a level of a detecting signal outputted by the LPF (Low Pass Filter) with a level of an adder signal. The APC amplifier, based on the comparison result, generates a gain controlling signal that makes a difference between a level of the detecting signal and level of the signal approach zero and feeds the gain controlling signal to a power amplifier. The power amplifier modulates the signal outputted from the amplifier by the gain controlling signal and power-amplifies the modulated signal according to a level of the gain controlling signal. Since the APC amplifier feeds the gain controlling signal to the power amplifier, a modulation degree does not depend on a nonlinear distortion characteristic of the power amplifier.

Abstract: A crystal has a diameter of 1 cm or more and shows a strongest peak in cathode luminescent spectrum at a wavelength of 360 nm in correspondence to a band edge.

Abstract: A crystal growth apparatus comprises a reaction vessel holding a melt mixture containing an alkali metal and a group III metal in a vessel space thereof, a porous member holding a metal melt by a surface tension thereof in a path through which a vapor of the alkali metal in contact with the metal mixture in the vessel space escapes to an external space, the porous member further supplying a nitrogen source gas fed from outside thereto further to the reaction vessel therethrough and through the metal melt by a pressure difference formed between the vessel space in the reaction vessel and the external space, and a heating apparatus heating the melt mixture to a crystal growth temperature.

Abstract: A method for manufacturing a group III nitride crystal on a seed crystal in a holding vessel holding therein a melt containing a group III metal, an alkali metal and nitrogen. The manufacturing method comprises the steps of causing the seed crystal to make a contact with the melt, setting an environment of the seed crystal to a first state offset from a crystal growth condition while in a state in which said seed crystal is in contact with the melt, increasing a nitrogen concentration in the melt, and setting the environment of the seed crystal to a second state suitable for crystal growth when the nitrogen concentration of the melt has reached a concentration suitable for growing the seed crystal.

Abstract: A crystal manufacturing apparatus for manufacturing a group III nitride crystal includes a crucible that holds a mixed molten liquid including an alkali metal and a group III metal; a reaction vessel accommodating the crucible in the reaction vessel; a heating device that heats the crucible with the reaction vessel; a holding vessel having a lid that is capable of opening and closing, accommodating the reaction vessel and the heating device in the holding vessel; a sealed vessel accommodating the holding vessel in the sealed vessel, having an operating device that enables opening the lid of the holding vessel for supplying source materials into the crucible and taking out a manufactured GaN crystal under a sealed condition, and closing the lid of the holding vessel that is sealed in the sealed vessel, the sealed vessel including an inert gas atmosphere or a nitrogen atmosphere; and a gas supplying device for supplying a nitrogen gas to the mixed molten liquid through each of the vessels.

Abstract: A crystal producing apparatus includes a crystal forming unit and a crystal growing unit. The crystal forming unit forms a first gallium nitride (GaN) crystal by supplying nitride gas into melt mixture containing metal sodium (Na) and metal gallium (Ga). The first GaN crystal is sliced and polished to form GaN wafers. The crystal growing unit grows a second GaN crystal on a substrate formed by using a GaN wafer, by the hydride vapor phase epitaxy method, thus producing a bulked GaN crystal.

Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.

Abstract: In a crystal preparing device, a crucible holds a mixed molten metal containing alkali metal and group III metal. A container has a container space contacting the mixed molten metal and holds a molten alkali metal between the container space and an outside of the container, the molten alkali metal contacting the container space. A gas supply device supplies nitrogen gas to the container space. A heating device heats the crucible to a crystal growth temperature. The crystal preparing device is provided so that a vapor pressure of the alkali metal which evaporates from the molten alkali metal is substantially equal to a vapor pressure of the alkali metal which evaporates from the mixed molten metal.

Abstract: A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.

Abstract: A crystal growth method of a group III nitride includes the steps of forming a melt mixture of an alkali metal and a group III element in a reaction vessel, and growing a crystal of a group III nitride formed of the group III element and nitrogen from the melt mixture in the reaction vessel, wherein the step of growing the crystal of the group III nitride is conducted while controlling an increase rate of degree of supersaturation of a group III nitride component in the melt mixture in a surface region of the melt mixture.

Abstract: A method of making a bulk crystal substrate of a GaN single crystal includes the steps of forming a molten flux of an alkali metal in a reaction vessel and causing a growth of a GaN single crystal from the molten flux, wherein the growth is continued while replenishing a compound containing N from a source outside the reaction vessel.

Abstract: In the case where an ultraminiature piezoelectric substrate, which has a resonating portion formed by making a concavity by etching in the surface of the piezoelectric substrate made of an anisotropic crystal material, is mass-produced by batch operation using a large-area piezoelectric substrate wafer, an annular portion surrounding each concavity is formed sufficiently thick to prevent cracking from occurring when the wafer is severed.