Silicon-Based Quantum MOS Technology Development

Abstract

Abstract : This program demonstrated the first compatible resonant tunneling diodes (RTD) for integration with CMOS (complementary metal oxide semiconductor) technology and designed circuits to exploit and evaluate the speed-power advantage of integrated RTD and CMOS devices. The first Si-based resonant interband tunnel diodes were demonstrated with peak current density greater than 10(exp 4) A/sq cm; peak-to-valley current ratio exceeding 2 was achieved at room temperature. The SiO2/Si/SiO2 RTD was studied extensively in a variety of forms, however no room temperature negative differential resistance was observed in the SiO2/Si/SiO2 system. Other double barrier systems were also studied including ZnS/Si, CaF2/Si, and Si3N4/Si without evidence of resonant tunneling. Circuit designs using SPICE showed that integration of tunnel diodes with CMOS provides typically more than 2x speed and density improvement for analog and digital circuits and more than 20x reduction in static power dissipation for memory over conventional circuit approaches. A roadmap was developed outlining the steps to commercialization.