Logic circuits using resonant-tunneling hot-electron transistors (RHETs)

A full adder and a 1/2 frequency divider using resonant-tunneling hot-electron transistors (RHETs) are proposed. These circuits make the best use of negative differential conductance, a feature of RHETs, and contain much fewer transistors than used in conventional circuits. They were fabricated using self-aligned InGaAs RHETs and WSiN thin film resistors on a single chip. The RHETs have an i-InGaAlAs/i-InGaAs collector barrier that improves the current gain at low collector-based voltages. Circuit operation was confirmed at 77 K with a supply voltage of 3 V.<
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