Comparison of Hydrazine, Dimethylhydrazine and T-butylamine Nitrogen Sources for MOVPE Growth of GaInNAs for Solar Cells

Dimethylhydrazine (DMHy) has been shown to be an effective nitrogen source for the growth of the alloy Ga_1-xIn_xN_yAs_1-y (x, y≪1). However, high DMHy flow rates are required, and low diffusion lengths and high p-type background doping concentration are typically observed in the grown material. It is therefore of interest to evaluate alternative nitrogen sources. Here, we evaluate two such sources: hydrazine and tertiarybutylamine. Hydrazine is of particular interest because it contains no carbon, suggesting that it might yield lower p-type background doping than DMHy does. With tertiarybutylamine, no nitrogen incorporation was observed, even with nitrogen/III ratios as high as 2000, and so does not appear promising. With hydrazine, by contrast, significant nitrogen incorporation was observed, even at much lower nitrogen/III ratios than would be required using DMHy. However, the p-type background doping appears no lower than with DMHy.