Vapor Phase Doping with N-type Dopant into Silicon by Atmospheric PressureChemical Vapor Deposition

摘要

Atomic layer doping of phosphorus (P) and arsenic (As) into Sirnwas performed using the vapor phase doping (VPD) technique. Forrnincreasing deposition time and precursor gas flow rate, the P andrnAs doses tend to saturate at about 0.8 and 1.0 monolayer of Si,rnrespectively. Therefore, these processes are self-limited in bothrncases. When a Si cap layer is grown on the P-covered Si(001), highrnP concentration of 3.7 × 1020 cm-3 at the heterointerface in the Sicap/rnP/Si-substrate layer stacks is achieved. Due to As desorptionrnand segregation toward the Si surface during the temperature ramprnup and during the Si-cap growth, the As concentration at thernheterointerface in the Si-cap/As/Si-substrate layer stacks was lowerrncompared to the P case. These results allowed us to evaluate thernfeasibility of the VPD process to fabricate precisely controlledrndoping profiles.