Design and manufacture of the carrier and flex cable for the Leonardo 1K

Leonardo partnered with the Institute for Astronomy (IfA), University of Hawaii to develop a 1K x 1K infrared avalanche photo diode suitable for low background science applications. Presented here is the design and thermal modeling for the Kovar carrier for mounting the detector as well as the challenges faced in designing and manufacturing the complex flex cable. The flex cable provides the 68 bond pads necessary to service the detector in a width of just over 17mm as well as providing filtering for the bias supplies. The final package is a compact, three side buttable package that has been successfully tested at an operating temperature of 80K.