The University of Tokyo

Tokyo University

Takashi Mukaibo

Takuo Sugano

Hideharu Miyake

Yoichi Okabe

Tatsuo Akiyama

Eiji Niki

Ho Q Vu

Naoki Fukaya

An intermittent etching process for forming efficiently by reactive ion etching (RIE), a minute recess, such as a groove having an opening width as small as about 0.1 .mu.m, with a large aspect ratio in layers of metals, semiconductors, etc. The process comprises alternating RIE steps of brief duration e.g. 30 seconds with vacuumizing for evacuating gaseous reaction products produced in the RIE step from the etched recess. The process is particularly suitable for formation of a bridging portion of Nb, etc. constituting Josephson devices, by making use of three layered resist technique.

Intermittent etching process

A superconducting logic circuit has a first and a second one-junction SQUID's (superconducting quantum interference device) connected by a superconducting inductor, the junction of the second SQUID having a larger critical current than that of the first SQUID, the inductance of the second SQUID being smaller than that of the inductor, and a signal applied to the first SQUID is unidirectionally transmitted to the second SQUID by applying bias currents to the junctions of the two SQUID's.

Unidirectional single-flux-quantum logic circuit

A semiconductor substrate is formed by irradiating a semiconductor substrate with radioactive ray so as to generate lattice defects therein for making the entire substrate semi-insulating and then rendering only the surface of the thus irradiated substrate semiconductive, so that a semiconductor device is produced by using the substrate thus formed.

Method of making semiconductor MOSFET device by bombarding with

An ion selective field-effect sensor selectively sensitive to a particular cation to be measured is disclosed. In the sensor is used a giant heterocyclic compound selectively forming a complex with the particular cation as an ion sensitive film provided on a surface of a field-effect semiconductor device.

Growing community of inventors

Tokyo, Japan

Takuo Sugano