A low-cost and high-performance transistor beyond CMOS is invented. The new transistor is a three-terminal device, called Quantum Wire Resonant Tunneling Transistor (QWRTT). The emitter/base/collector regions comprise metal quantum wires embedded in semiconductor. The quantum wires are formed by implantation of metal ions with suitable work functions to the semiconductor along the open channel direction. The QWRTT has very small swing (< 10 mV/dec) because the current conduction mechanism is the resonant tunneling effect and the quantum wires have 1-D density of states. The QWRTT has the following potential advantages over the MOSFET in digital circuit applications. The QWRTT can operate at higher speed and consume less power because of its smaller swing and lower power supply voltage. The manufacturing cost is lower because of its simpler device structure and less number of process steps. The QWRTT has better reliability and better uniformity because it does not rely on gate dielectrics and doping. A QWRTT can be configured as a normally on transistor with VON = 0 V, an enhancement-mode transistor with positive VON, or an enhancement-mode transistor with negative VON. The QWRTT circuit design can be more diversified and efficient than the CMOS circuit design. The entire digital circuits can be constructed using only one type of devices such as the n-type devices. Using only one type of devices to construct digital circuits has the following major advantages over the combination of both n- and p-type devices such as better circuit performance, better current matching, and lower manufacturing cost.