Thermally matched readout/detector assembly and method for fabricating same

• Main Authors: RONALD M FINNILA, GERARD T MALLOY, JOSEPH J BENDIK
• Format: Patent
• Language: English
• Published: 20.11.1996
• Edition: 6
• Subjects: BASIC ELECTRIC ELEMENTS; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SEMICONDUCTOR DEVICES; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

An intergrated circuit assembly includes a silicon thin film circuit bonded to a substrate of a material selected to provide the assembly with an effective thermal expansion characteristic that approximately matches hat of another device, such as HgCdTe detector. The assembly, when bump bonded with the device, is resistant to failure when subjected to thermal cycling. A first method for manufacturing the assembly includes the steps of forming a desired circuit in a thin layer (12) of silicon on a silicon substrate of a bonded silicon wafer. The thin silicon layer including the circuit is is then bonded to the selected substrate material (24). Thereafter the silicon substrate is removed and the resulting assembly may be mated to the device (36). A second method employs a two stage transfer technique wherein the processed thin silicon layer is bonded to a first, temporary substrate; the silicon substrate is removed; a second, permanent substrate is attached; and the first substrate is removed. The second substrate is comprised of a material selected for providing the assembly with a coefficient of thermal expansion that is matched to the material of the device.