InAs Electron-Hole Bilayer LED

We report a novel switched-mode light-emitting device (LED) in an undoped ultra-thin body (UTB) InAs channel based on the electrostatically induced electron-hole (EH) bilayer concept. The induced EH channels at their respective gate interfaces, which remain spatially separated in steady state, gradually diffuse and recombine during a switch-off transient. Using TCAD simulations, we show that continuous switching of the gates with a ~12 μs time period leads to radiative recombination of the induced charge carriers with a peak internal quantum efficiency (IQE) as high as ~92%. The proposed concept obviates the need for chemically doped p-n junctions in the UTB device for light emitting applications and could also be employed for other direct bandgap semiconductors. However, the switching speed is ultimately limited by the thermal generation time.