Characterization of Ion Implanted Silicon Annealed with a Graphite Radiation Source
A Varian IA-200 isothermal annealer has been used to anneal ion implantation damage and electrically activate dopants in As and B implanted silicon with minimal redistribution of the impurity. The anneal occurs in vacuum using infrared radiation from a resistively heated sheet of graphite. Good quality anneals of /sup 11/B implanted samples have been obtained with minimal boron diffusion. Arsenic implanted wafers have also be annealed with excellent results except for a substantial loss of As which occurs unless the wafer has an SiO/sub 2/ cap. The anneal quality of (100) wafers was independent of dose, however, the anneal quality of the (111) wafers improved with increasing As dose.
Transient annealing of ion implanted semiconductor materials
Abstract Rapid thermal processing using a Varian IA-200 annealer has been applied to a variety of ion implanted samples. Single crystal silicon has been implanted with As, P, or B to doses of 1 × 10 13 /cm 2 to 1 × 10 16 /cm 2 and annealed. Complete activation can be achieved with minimal diffusion and no loss of dopant if the samples are capped with SiO 2 . Residual damage has been analyzed by Rutherford backscattering. The residual damage depends on implant dose and wafer orientation [(100) vs (111)] as well as anneal conditions. Polycrystalline Si films on oxidized Si wafers have been implanted with As, B or BF 2 and subjected to a transient anneal. Dopants diffuse faster and As is lost from polycrystalline Si faster than single crystal Si if the films are not capped. Sheet resistance of polycrystalline Si films after transient annealing are less than after furnace annealing. Diodes and transistors have been implanted and subjected to a transient anneal. The leakage currents, lifetimes and betas are as good or better than conventional anneals.
17 &mgr;m pixel 640 x 480 microbolometer FPA development at BAE Systems
BAE Systems has developed an advanced 640 x 480 focal plane array (FPA) with a 17 &mgr;m pixel pitch. Sensitivity of ≤ 50 mK was demonstrated and the FPAs were used in imaging demonstrations. Successful scaling of BAE Systems' patented single contact per pixel, single-level microbolometer process to 17 &mgr;m pitch provides a path toward next generation microbolometer imaging systems.