Semicoa, a Costa Mesa, Calif., maker of photodectors used in medical imaging, homeland security and military aerospace applications, recently hired George Papadopoulos as director of wafer fabrication engineering and operations. He will manage the company's optoelectronics technology manufacturing and wafer fabrication expansion, which it said will involve developing products for visible and near-infrared silicon applications. Papadopoulos formerly held manufacturing engineering and process development positions at IQC, a biophotonics startup, and at NanoOpto. He was previously silicon wafer fabrication engineering manager at Perkin Elmer Optoelectronics. . . . Thermoteknix Systems Ltd., an infrared camera manufacturer for industrial, surveillance and military markets, has moved its headquarters to a larger building in Cambridge, England. Its new address is: Teknix House, 2 Pembroke Ave., Waterbeach, Cambridge CB5 9QR UK. The new phone number is +44 (0)1223 204000; fax: +44 (0)1223 204010.