InP-based monolithically integrated RTD/HBT MOBILE for logic circuits

A pseudo dynamic logic family is developed on InP-substrates based on the MOBILE concept. The conventional HFET as input terminal is replaced by a monolithically integrated series combination of a HBT and a RTD forming a RTBT. This combination enables a logic function defined by the RTD area only. The HBT provides a robust enhancement type operation, although for full level compatibility a buffer inverter is still necessary. A novel distributed clocking scheme is developed. The feasibility of this logic concept is experimentally verified and an OR gate is discussed in detail.