Chemical beam epitaxy of GaAs_1-xN_x using MMHy and DMHy precursors, modeled by ab initio study of GaAs(100) surfaces stability over As₂, H₂ and N₂

Using ab initio calculations, a simple model for GaAs_1-xN_x vapor-phase epitaxy on (100) surface of GaAs was created. By studying As₂ and H₂ molecules adsorptions and As/N atom substitutions on (100) GaAs surfaces, we obtain a relative stability diagram of all stable surfaces under varying As₂, H₂, and N₂ conditions. We previously proved that this model could describe the vapor-phase epitaxy of GaAs_1-x N_x with simple, fully decomposed, precursors. In this paper, we show that in more complex reaction conditions using monomethylhydrazine (MMHy), and dimethylhydrazine (DMHy), it is still possible to use our model to obtain an accurate description of the temperature and pressure stability domains for each surfaces, linked to chemical beam epitaxy (CBE) growth conditions. Moreover, the different N-incorporation regimes observed experimentally at different temperature can be explain and predict by our model. The use of MMHy and DMHy precursors can also be rationalized. Our model should then help to better understand the conditions needed to obtain an high quality GaAs_1-xN_x using vapor-phase epitaxy.