A simple method for the open-tube diffusion of Zn from (ZnO)x(SiO2)1-x film sources, and into GaAs was described. The oxide films were deposited by using metal-organic chemical vapor deposition. A capping layer of SiO2 was deposited on top of the source films, and diffusion was carried out in flowing N at 650C. Diffusion depths of between 200nm and several microns could be easily obtained. The diffusion front in n-type substrates was sharp. The dependence of the diffusion depth upon the source film composition (for x-values of 0.04 to 1) was determined by using sectioning methods.
D.J.Lawrence, F.T.Smith, S.T.Lee: Journal of Applied Physics, 1991, 69, 3011-5