Influence of growth temperature and cooling rate on the growth of Si epitaxial layer by dropping-type liquid phase epitaxy from the pure Si melt

Abstract

This work deals with liquid phase epitaxy (LPE) from pure Si melt, which has been proposed as a method to grow Si thin layer crystals without suffering from incorporation of solvents in contrast to conventional LPE. Dropping-type LPE from pure Si melt was employed to independently control substrate temperature and cooling rate. We found that the Si epitaxial layer could be obtained in a wide temperature window even at the temperatures of 200 °C lower than the Si melting point, which demonstrates the feasibility of the proposed method. With the increase of substrate temperature, the etch pit density of epitaxial layer decreased and minority carrier diffusion length increased. Furthermore, the decrease in the cooling rate after the LPE growth was found to improve the quality of Si epitaxial layer. This shows that substrate temperature and cooling rate after the LPE growth are the key growth-controlling parameters.