Millisecond flash lamp annealing of shallow implanted layers in Ge

Abstract

Shallow n+ layers in Ge are formed by phosphorus implantation and subsequent millisecond flash lamp annealing. Present investigations are focused on the dependence of P redistribution, diffusion and electrical activation on heat input into the sample and flash duration. In contrast to conventional annealing procedures an activation up to 6.5× 1019 cm-3 is achieved without any dopant redistribution and noticeable diffusion. Present results suggest that independently of pretreatment the maximum activation should be obtained at a flash energy that corresponds to the onset of P diffusion. The deactivation of P is explained qualitatively by mass action analysis which takes into account the formation of phosphorus-vacancy clusters

High performance germanium n-MOSFET with antimony dopant activation beyond 1×10²⁰ cm^−3

“…These junctions are integrated with SPA GeO 2 High-k gate stack to obtain a high performance Ge nMOSFET with significantly reduced contact resistance. Ion Implantation RTA Sb-8 x 10 18 / As 8x10 18 / P-2x10 19 /B-1x10 20 [6] Ion Implantation Flash Anneal P -6x10 19 [7] In-situ doping Thermal P-1x10 19 [8] Gas Phase Doping RTA As-1x10 19 [9] Ion Implantation Furnace Anneal P -8 x 10 18 [10] Ion Implantation Laser Thermal Processing (LTP) …”

Germanium Doping, Contacts, and Thin-Body Structures

“…In Si applications high-temperature millisecond anneals (laser and flash) are popular and are beginning to be applied to Ge (37)(38)(39)(40). As the melting point of Ge is 937 °C, a low-temperature process such as solidphase-epitaxial-regrowth appears to be another solution (41).…”

Diffusion ofn-type dopants in germanium

“…Thereby enhanced diffusion due to implantation damage is also suppressed. For example, W€ undisch et al 64,88 have demonstrated by millisecond flash lamp annealing of shallow P implants that an electric active P concentration of about 6.5 Â 10 19 cm À3 can be realized without noticeable P diffusion. Similarly, high concentrations of electrically active As and Sb were obtained by laser annealing of As-and Sb-implanted Ge.…”