A planar process for manufacturing large silicon detectors on a 100 mm wafer has been developed. Several oxidation and annealing temperatures were studied in order to optimize detector performance. A strip detector with an active area of 32 X 58 mm2 together with various single detector diodes were processed and tested. The 1280 strip detector with 25-mu-m strip and readout pitch was connected to multiplexing LSI electronics and tested with tracks from a Sr-90 beta source. The most probable signal pulse height was found to be 14 times the sigma-noise of any individual channel.