Laser Epitaxy Over Buried Layers

The redistribution of antimony impurity atoms implanted in (111) and (100) substrates was studied as a function of the power density of Q-switched YAG laser radiation (λ = 0.53μm) used to recrystallize 4700Å films of amorphous silicon vapor deposited over blanket and patterned Sb buried layer structures. Results for fully crystallized layers show impurity profiles ranging from a sharp interface displaced outward slightly relative to the as-grown interface, to complete redistribution of antimony into the deposited layer. Studies of patterned buried layer structures indicate that epitaxial crystallization can be achieved on (111) and (100) substrates without serious damage to the surface topography necessary for subsequent mask alignment.