An Analysis of Arsenic Ion Implantation for Use in Silicon Bipolar Devices
A study was made of arsenic ion-implantation in silicon for use in bipolar integrated circuits. Ion beam energies in the range 10 to 320 keV were used to implant 2 × 1015 to 2 × 1016 arsenic ions/cm2 into the silicon. Annealing was carried out at temperatures in the range of 900 to 1250°C in the presence of oxygen. Electron channelling with a scanning electron microscope showed that the combination of the oxygen and the higher temperature anneals was adequate to produce a high quality single crystal surface.
Back-scattering experiments with 2 MeV helium ions confirmed the good quality single crystal nature of the surface. A careful analysis of the back-scattering random and aligned energy spectra showed that a high percentage of the arsenic atoms were substitutional in the crystal lattice. This high percentage was confirmed by surface resistivity and diffusion profile measurements. The surface resistivity variation in the implanted layers was better than 3%.
KeywordsSheet Resistance Epitaxial Layer Arsenic Atom Energy Sheet Arsenic Diffusion
Unable to display preview. Download preview PDF.
- (1).“C.D.I. and Competitive Techniques” by G. Bruchez, Microelectronics, 5, No. 4, p.45, 1974.Google Scholar
- (2).This conference and “Measurement of doping uniformity in semi-conductor wafers” by B.J. Smith, J. Stephen and G.W. Hinder, A.E.R.E., Harwell Report R-7085, 1974.Google Scholar
- (3).“Diffusion of ion implanted antimony and arsenic in silicon”. C.M. Drum Abstract 84. Extended Abstracts Vol. 74–1 Electrochemical Society. May 1974.Google Scholar