InAs quantum dots as charge storing elements for applications in flash memory devices

Abstract

Abstract InAs quantum dots (QDs) were grown by metal organic chemical vapor deposition technique to use them as charge storage nodes. Uniform QDs were formed with average diameter 5 nm and height 5–10 nm with a density of 2 × 10 11 cm −2 . The QDs were grown on high-k dielectric layer (ZrO 2 ), which was deposited onto ultra-thin GaP passivated p-GaAs (1 0 0) substrate. A charge storage device with the structure Metal/ZrO 2 /InAs QDs/ZrO 2 /(GaP)GaAs/Metal was fabricated. The devices containing InAs QDs exhibit superior memory window, low leakage current density along with reasonably good charge retention. A suitable electronic band diagram corresponding to programming and erasing operations was proposed to explain the operation.