Influence of the carrier Gas, trimethylgallium flow, and growth time on the character of the selective epitaxy of GaN

The influence of the carrier gas, trimethylgallium flow, and growth time on the character of the selective epitaxy of GaN in stripe windows oriented along the crystallographic direction $\langle\bar{1}100\rangle$ GaN for various widths of the mask between the stripes is studied. It is shown that the addition of nitrogen in the reactor atmosphere leads to changes in the form of the stripes in the case of wide (40 $\mu$m) mask from a rectangular form restricted by a $\{1\bar{1}20\}$ lateral face to a trapezoidal form restricted by a $\{1\bar{1}22\}$ lateral face. It is also shown that during growth in the nitrogen-hydrogen mixture, the gallium flow starts to considerably affect the form of the growing stripes. It is shown that the process is significantly unstable, which leads to a noticeable variation in the form type as the transverse section of the stripe increases.