It’s All About Electric Field Energy…
All Field Effect Transistors (FETs) create current in proportion to the energy in an electric field defined by gate-source potential and stored in the gate structure. This field induces a potential across a highly resistive material (most commonly, a semiconductor). The energy transferred from the gate capacitance to the resistive material reduces the material’s resistance, enabling current to increasingly flow as the potential across the resistive material increases.
…with a lot of help from Amorphous Metals
Increasing gate electric field energy increases transconductance of the TFT. However, increasing electric field energy brings with it complications. Non-uniformities across the gate electric field translate to non-uniformities in the surface potential induced on the resistive material. Those non-uniformities increase charge scattering in the resistive material’s conduction channel, reducing transconductance.
Amorphous gate metal’s uniquely smooth surface reduces non-uniformities in the gate electric field energy and at the gate insulator-semiconductor interface, reducing charge scattering in the conduction channel. This enables the full transconductance benefit created by increasing gate electric field energy.
