摘要 |
The deposition of an epitaxial silicon layer onto a monocrystalline silicon substrate from a silicon carrier gas may be effected by decomposing the silicon carrier gas on the substrate during a high temperature heat pulse. Removal of oxide from the substrate before deposition is effected on heating the substrate to over 1000 DEG C at the start of the heat pulse 41 in the presence of the silicon carrier gas. Deposition is effected while the substrate is maintained at a high temperature 42 and the deposition is terminated by allowing the substrate temperature to fall to a temperature below the minimum at which epitaxial deposition occurs. A radiantly heated reactor is used to obtain high rates of temperature rise and fall, for example 20 DEG C to 1150 DEG C in 12 seconds 41. Thin undoped layers may be grown on highly doped substrates with small transition depth D, for example, a 0.43 mu m epilayer on a substrate having an arsenic concentration of 2.4x10<25>m<-3>, has D = 62nm. Such a method is particularly useful in the production of VLSI devices. <IMAGE> |