Investigation of surface pretreatments on GaAs and memory characteristics of MOS capacitors embedded with Au nano-particles

In this work, we have fabricated the first non-volatile memory of metal–oxide–semiconductor (MOS) capacitors embedded with Au nano-particles on GaAs substrate. After 800 °C RTA annealing for 30 s, the Au nano-particles with a narrow size distribution can be self-assembled from an ultrathin Au layer sandwiched in the gate oxide. From loop C–V measurement, large hysteresis phenomenon can indicate charge storage effect. Moreover, the GaAs substrates were pretreated by HCl(10%) + NH4OH(1%), (NH4)2SX, and P2S5/(NH4)2SX solutions before tunneling oxide deposition to reduce the GaAs native oxide related surface states. Owing to the stable phosphorus oxides and sulfur bound to the Ga and As species can be efficient obtained by using P2S5/(NH4)2SX pretreatment; therefore, lowest leakage current was also observed in Al/GaAs schottky diodes with this process.