Superconductive integrated circuit device

Abstract

Abstract PURPOSE:To integrate the whole in high density, and to prevent reduction of signal current values in layers for electrode and wiring of a superconductive circuit device by a method wherein necessary regions in a layer for earthing of superconductive are changed into regions of a superconductive phase having a superconductive transitional temperature lower than the temperature of a layer of nonsuperconductive phase or the layer for earthing. CONSTITUTION:A Josephson junction 11 is formed on a substrate 1 through a layer 4 for earthing of superconductor, insulating layers 2, 5, etc., and layers 6, 10 for superconductor electrode or wiring and windows 7 are provided in the junction 11 thereof. An ion implantation process of proton, He<+>, N<+>, Ne<+>, Ar<->, O<+>, Ga<+>, etc., is performed into the prescribed regions 20 in the layer 4 for earthing without forming a step part in the layer 6 for electrode or wiring, and the regions 20 are changed from the layer 4 for a nonsuperconductive phase or earthing into a superconductive phase having a superconductive transitional temperature. Accordingly, the whole of the superconductive integrated circuit device can be formed in high density, reduction of critical currents to flow into the layers 6, 10 for electrode or wiring is prevented, and signal current values are enlarged.

Inventors

• 👤 Takao Waho
• 👤 孝夫 和保
• 👤 Goji Kawakami
• 👤 剛司 川上
• 👤 Fumihiko Yanagawa
• 👤 柳川　文彦

Bibliographic Details