Extremely low temperature formation of silicon dioxide on gallium arsenide

This article demonstrates the growth of silicon dioxide (SiO2) on a gallium arsenide (GaAs) substrate by use of the liquid phase deposition (LPD) method at extremely low temperature (similar to 40 degrees C). This method cannot only grow SiO2 but it can also obtain good quality and reliability due to the suppression of interdiffusion in such a low temperature process. The deposition rate of LPD-SiO2 on GaAs is up to 1265 Angstrom/h. The refractive index of the LPD-SiO2 film on GaAs is about 1.42 with growth at 40 degrees C. When the LPD-SiO2 film on the GaAs substrate is used to fabricate a metal-oxide-semiconductor capacitor with a device area of 0.3 cm(2), the surface charge density (Q(ss)/q) is about 3.7x10(11) cm(-2) and the leakage current is 43.3 pA at -5 V. A proposed mechanism for the LPD of SiO2 on GaAs is also presented. (C) 1997 American Institute of Physics.