Zaidan Hojin Handotai Kenkyu Shinkokai

Junichi Nishizawa

Yasuo Okuno

Jun-ichi Nishizawa

Keishiro Takahashi

Kazuomi Ito

A solution growth apparatus for conducting an epitaxial growth of a compound semiconductor crystal from solution by relying on the temperature difference technique at a constant growth temperature and on a mass production scale without deranging the control of the growth temperature applied externally of the growth apparatus and with the application of only a small heating power and only a small cooling power, by enhancing the thermal exchange efficiency through the provision of heating means, via an insulator, for the melt-containing reservoir provided on the growth boat housed within a quartz reactor and by the provision of cooling means at the bottom of the boat within the reactor.

Apparatus for performing solution growth relying on temperature

A method of forming a pn junction with a Group IIB-VIB compound semiconductor containing Zn is disclosed, the method including preparing an n type semiconductor region either locally or entirely in a Group IIB-VIB compound semiconductor crystal obtained by relying on a crystal growth method in liquid phase using a temperature difference technique, and subjecting this crystal to a thermal annealing in a Zn solution or in a Zn atmosphere to produce an n type region. Crystal growth is conducted while controlling the vapor pressure of the constituent Group IVB element to produce a p type region. A combination of all these steps gives a more stable pn junction.

Method of fabricating a semiconductor pn junction

A light-responsive light-emitting diode display comprises a light-emitting diode circuit including a series connection of light-emitting diodes and a light-responsive current-controlling circuit connected in series to said light-emitting diode circuit for supplying a current thereto in correspondence with the ambient brightness. A unipolar photo-transistor can provide a current above a predetermined minimum value and increasing with the intensity of incident lights and can absorb excess voltages when applied. Light-responsive current-control reduces the useless power dissipation, and all solid-state display provides a very long service life.

Light-responsive light-emitting diode display

A plurality of light-emitting diodes are connected in series to elevate the working voltage. A plurality of said series connection are connected in parallel to maintain display even upon a disconnection accident. The total number of light-emitting diodes provides a bright and failure-safe colored light display at a low power consumption. The conventional colored-light-emitting display can be easily substituted by the novel light-emitting diode display to reduce the power consumption and elongate the service lifetime.

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Sendai, Japan

Yasuo Okuno