SELECTIVE-AREA GROWTH OF INP BY PLASMA-ASSISTED SOLID-SOURCE EPITAXY

Complete selective area growth of InP could be achieved at standard mo lecular beam epitaxial growth temperatures by using solid source epita xy with an additional hydrogen rf-plasma (27 MHz) excited in the react ion chamber. By optimization of the process parameters such as substra te temperature, plasma power, and phosphorus overpressure, mirror-like InP-layers with geometry independent growth rates were grown on SiN-p atterned InP substrates without polycrystalline growth on the mask. Si nce selective growth is also possible in an argon plasma, we conclude that a physical desorption process is the mechanism for selective area growth in this plasma assisted epitaxy method. Furthermore, the selec tivity can be controlled by a de-bias of the substrate, which influenc es the mean energy of the impinging ions, thereby changing the desorpt ion rate of atoms from the mask.