GaAs Tunnel Diode With Electrostatically Doped n-Region: Proposal and Analysis

In n-type GaAs, the electron concentration saturates to a value close to 10¹⁹ /cm³ even when the chemically doped impurity concentration is more than the value. Therefore, the peak current density in GaAs-based tunnel diodes is limited by the difficulty in realizing the n-type GaAs using dopant diffusion. In this brief, we demonstrate that the n-type region can be electrostatically induced in p-type GaAs using a metal electrode of appropriate work function. This obviates the need for n-type chemical impurity doping in GaAs. Using calibrated 2-D simulations, we demonstrate that the proposed GaAs tunnel diode with electrostatically doped n-region on p-type GaAs not only exhibits significantly improved peak current but also is easy to fabricate.