IEEE Transactions on Applied Superconductivity

Implementation and Experimental Evaluation of a Cryocooled System Prototype for High-Throughput SFQ Digital Applications

Y. Hashimoto, Shinichi Yorozu, Toshiyuki Miyazaki, Y.. Kameda, Hideo Suzuki, Nobuyuki Yoshikawa

Published Jun 1, 2007• 42 citations

Abstract

We report on development of a cryocooled system prototype for high-throughput single flux quantum (SFQ) digital applications. The system was designed to have 32 I/O links with a bandwidth of 10 Gbps/port. An SFQ multi-chip module (MCM), double mu-metal magnetic shields, a 40-K radiation shield, customized GaAs cryogenic amplifiers, a 32-pin wide-bandwidth cryo-probe, and 32 I/O cables were packaged in a vacuum chamber together with a two-stage 4-K 1-W Gifford-McMahon (G-M) cryocooler. S-parameter measurements showed that the analog bandwidth of the I/O link was 23 GHz. We demonstrated high-speed cryocooled operation of a test module, in which a 5 mm times 5 mm SFQ circuit chip was flip-chip bonded on a 16 mm times 16 mm MCM carrier with phi30 mum InSn bump bonds, at bit rates up to 12.5 Gbps. Measured bit error rate (BER) was less than 10-12for a 1023- 1 pseudorandom bit sequence (PRBS) at 10 Gbps.

DOI: 10.1109/tasc.2007.898126

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