Energy-Filtered Tunnel Transistor: A New Device Concept Toward Extremely Low Energy Consumption Electronics

Altering the thermal characteristics of semiconductors can prolong battery life.

Office of Naval Research, Arlington, Virginia

Excessive heat dissipation (or power consumption) of modem integrated circuits is an undesirable effect that imposes substantial limitations on the performance of many electronic devices. For example, the level of heat dissipation /power consumption of smart phones, tablets, and laptops is such that it prohibits a continuous and prolonged operation of these devices, requiring frequent recharging. Large power consumption of electronic devices requires large energy storage in batteries, increasing the battery weights that soldiers carry in their missions or the weights of remote controlled equipment such as unmanned aerial vehicles (UAVs). Therefore, technology that enables electronic devices to operate with extremely small energy consumption promises a broad range of commercial, military and space applications.

The root cause of heat dissipation of current metal-oxide-semiconductor field effect transistors (MOSFETs) is the thermal excitation of electrons that obeys thermodynamics, i.e., the Fenni-Dirac energy distribution of electrons. The thermally excited electrons at the tail of the Fenni-Dirac distribution can overcome the energy barrier set in the OFF state of the MOSFETs. This causes substantial OFF state leakage currents even after the gate voltage is reduced below the threshold voltage, resulting in large heat dissipation or energy consumption for integrated circuits. The challenge for this large heat dissipation is that its root cause is an intrinsic phenomenon of thermodynamics (Fermi-Dirac distribution) that cannot be directly manipulated.