A Novel Atomic Layer Epitaxy Method of Silicon

A new atomic layer epitaxy (ALE) method of silicon has been investigated. Substrate temperature T s is increased to more than a critical temperature, and decreased to less than another critical temperature alternatively, and trisilane gas is injected as source molecules only in a short interval within the low-T s phase. This method separates an adsorption phase of silicon hydrides with one-monolayer thickness from a desorption phase of hydrogen, resulting in the monolayer growth per cycle. ALE growth conditions were estimated from gas-source MBE characteristics, and ALE growth (with 0.8 monolayer/cycle) was demonstrated. The grown layer had good surface morphology and crystallinity.