Abrupt doping by atomic beams in chemical beam epitaxy.

The use of chemical beam epitaxy (CBE) instead of chemical vapor deposition (CVD) allows the incorporation of thermal atomic beams for doping. This combination produced ultra- thin and very abrupt dopant profiles similar to those achieved in conventional molecular beam epitaxy (MBE). Dopant profile measurements by differential capacitance (Polaron) technique and secondary ion mass spectroscopy (SIMS) technique show that Si dopant in InP is extremely abrupt at all growth temperatures (<=600C) and there is no surface segregation. On the other hand, Sn dopant and to a lesser extend Be dopant show surface segregation which can be reduced by growing which can be reduced by growing the InP at lower temperature (<=550C). From this study, it is seen that Si should be preferred as the n-type dopant in producing InP/InGaAs high electron mobility transistor.