A silicon MOSFET/field emitter array fabricated using CMP

Si-based field emitter arrays (FEAs) are being studied as electron emitters in field emission displays (FEDs) due to their compatibility with Si IC technology. Si FEA performance has two major problems: (1) high addressing voltages and (2) nonuniform and unstable emission current. In a field emitter, emission current consists of two serial processes: electron flux to the surface and electron transmission through the barrier. A device that integrates FEAs with MOSFETs allows two modes of emission current control. When a low voltage is applied to the FEA gate, emission current is determined by electron transmission through the barrier. At high FEA gate voltages, emission current is determined by electron flux to the barrier; thus emission current is controlled by the transistor. Noise in field emission devices is caused by barrier height fluctuations due to adsorption/desorption of gases. A device controlled by electron supply rather than barrier transmission reduces noise significantly. In this paper, a LD-MOSFET is added in series with Si FEAs, leading to a device whose emission current is controlled by the MOSFET gate. Light doping at the drain region reduces the maximum electric field; impact ionization and avalanche multiplication are thus reduced or eliminated. The LD-MOSFET is expected to stabilize the current and lower the switch voltage of the FEA. The goal is to demonstrate FEA current control with a MOSFET.