Development of a Low Cost, Cryogenic Refrigeration System for Cooling of Cryoelectronics

Abstract

The use of multicomponent mixtures of FreonsTM or the light hydrocarbons with argon or nitrogen in a single stream, cascade, throttle expansion refrigeration cycle first suggested by Klimenko, provides it unique means for obtaining low cost refrigeration in the temperature range from 80K - 160K. This is suitable for the cooling of CMOS, HEMT, superconducting and other small cryoelectronic devices, and is an attractive choice because of the high overall thermodynamic effIciency attainable, and long operating life. Recent progress in the calculation of the thermodynamic properties of such mixtures and more detailed, multi-zone calculation of the properties of heat exchangers should make it possible to optimize the performance of these refrigerators. In addition, progress made in the fabrication of heat exchangers of high effIciency and simple construction will help to keep the system costs low. We report on these developments and their implementation to optimize the performance of a small, closed-cycle refrigeration system suitable for the cooling of CMOS multichip modules.