The broader impact/commercial potential of this I-Corps project is that the project device has the potential to become the next generation of ultra-low power devices. Tunnel Field Effect Transistors (TFETs), especially those with type III-V heterostructures, are excellent candidates to overcome both size and power scaling issue of Silicon metal?oxide?semiconductor field-effect transistor (Si MOSFET). III-V heterojunction TFET can easily achieve low power consumption by having high on-current and low off-current within a very short range of applied voltage. One of the bottlenecks for III-V materials to become mainstream is the lack of integration with current silicon manufacturing technology. The proposed device demonstrates technology that is compatible with silicon manufacturing technology which has the most commercial impact compared to any other III-V materials devices as it does not require any changes in the existing manufacturing process. By realizing this device, it will open the opportunity to replace the current existing FinFET technology in cellphone and computers, making a new generation of portable devices for logic applications and enabling ever-connected internet of things applications.
This I-Corps project proposes to create a low power tunneling field effect transistor (TFET) on a silicon substrate using novel fabrication techniques. The device employs InAs/AlSb/GaSb junction as the tunneling junction. This unique junction produces effective modulation of electron tunneling under control of the applied gate bias. The tunneling barrier AlSb layer is sandwiched between InAs and GaSb. This configuration allows the free band movements between InAs and GaSb. This unique junction is combined with a fin type channel structure to allow effective control over the active channel region by the surrounding gate metals. The fin device architecture will allow excellent gate electro-static control, and combining it with the tunneling mechanism will enable the fabricated devices to achieve a subthreshold slope much smaller than 60mV/dec. Another unique aspect of the proposed design is the use of elevated asymmetric T-shaped source and drain.
