A DIFFUSION-MODEL FOR SELECTIVE-AREA EPITAXY BY METALORGANIC CHEMICAL-VAPOR-DEPOSITION

A single-species diffusion model for selective-area epitaxy by metalor ganic chemical vapor deposition (MOCVD) has been developed. The model is solved analytically using conformal mapping and a new parameter, be ta, which accounts for the probability that an organometallic compound will reach the window by surface diffusion on the mask. The model cor rectly predicts the trends observed in selected-area growth rates with mask and window sizes. The model also reveals that different values o f beta for the group III sources leads to a dependence of the alloy co mposition on the feature size. This new model can be used as a design tool to identify mask materials and process conditions leading to succ essful selected-area growth processes.