A receiver unit for use in a CDMA system and including a channel processor, a buffer, and a data processor. A conductive film is formed on the transition metal boride layer. The filter circuitry, the compression circuitry, the correlation circuitry and the interpolation circuitry are all advantageously embodied in an on-chip digital signal processor. When a forward direct current gate voltage is applied to a gate terminal with a source terminal coupled to ground, the DC gate voltage becomes greater than or equal to 0.