Mitsui Engineering and Shipbuilding Company Limited

Kazuhiro Ozaki

Naoki Uchida

Keiji Kawanaka

Yoshihiro Okazaki

Hideyuki Nanba

A semiconductor substrate thermal treatment apparatus enables excellent heating control in suppressing influence of mutual induction between induction heating coils even when the induction heating coils are arranged in the vertical direction while providing horizontal magnetic flux to susceptors. The apparatus indirectly heats wafers mounted on horizontally-arranged susceptors including induction heating coils to form alternate-current magnetic flux in a direction parallel to a mount face of the susceptor. The wafer are arranged at an outer circumferential side of the susceptor. The induction heating coils are structured with at least one main heating coil and subordinate heating coils electromagnetically coupled with the main heating coil. Inverse coupling coils inversely-coupled to the subordinate heating coils are provided to the main heating coil, and zone control means separately controls a power ratio while synchronizing frequencies and current waveforms of current to the main heating coil and adjacent subordinate heating coils.

Induction heating apparatus and induction heating method

The purpose of the present invention is to minimize switching losses of an inverter. An induction heating device includes: a plurality of induction heating coils () which are disposed adjacent with each other; a plurality of inverters (), each of which has a capacitor () serially connected to each of the induction heating coils (), and converts a DC voltage into a square wave voltage; and a control circuit () which controls so as to align the phase of coil currents flowing though the plurality of the induction heating coils (), wherein the control circuit () controls the timing at which the square wave voltage transitions such that an instantaneous value of the square wave voltage is preserved in either the DC voltage or a turnover voltage, when the coil current zero crosses.

Induction heating device, induction heating method, and program

It is an object of the present invention to prevent temperature decrease in a border portion of each of heating coils and to enable to eliminate an influence given by the change in a load state. In order to attain this object, an induction heating unit according to the present invention is provided with control units respectively corresponding to a plurality of heating units. A phase detector of the control unit obtains a phase difference between an output current (heating coil current) of an inverter detected by a current transformer reference signal outputted by a reference signal generating section, and inputs it to a drive control section. The drive control section adjusts an output timing (phase) of a gate pulse to be given to the inverter so as to make a phase of the heating coil current of the inverter coincide with a phase of the reference signal outputted by the reference signal generating section. A phase control section controls a variable reactor so as to make the phases of an output voltage and the output current (heating coil current) of the inverter coincide with each other, and improves a power factor of the inverter. Each of the other control units also performs the same control operation.

Induction heating method and unit

It is an object of the present invention to prevent temperature decrease in a border portion of each of heating coils and to enable to eliminate an influence given by the change in a load state. In order to attain this object, an induction heating unitaccording to the present invention is provided with control units(to) respectively corresponding to a plurality of heating units(to). A phase detectorof the control unitobtains a phase difference between an output current (heating coil current IL4) of an inverterdetected by a current transformerand a reference signal outputted by a reference signal generating sectionand inputs it to a drive control sectionThe drive control sectionadjusts an output timing (phase) of a gate pulse to be given to the inverterso as to make a phase of the heating coil current IL4 of the invertercoincide with a phase of the reference signal outputted by the reference signal generating sectionA phase control sectioncontrols a variable reactorso as to make the phases of an output voltage and the output current (heating coil current IL4) of the invertercoincide with each other, and improves a power factor of the inverter. Each of the other control unitstoalso performs the same control operation.

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Tamano, Japan

Kazuhiro Ozaki