The transient enhanced diffusion of implanted boron has been examined by secondary ion mass spectrometry in crystalline silicon, in germanium preamorphized silicon, and in germanium amorphized and epitaxially regrown material. The total germanium dose used for amorphization of the silicon crystal was 1.2×1015 ions/cm2. The transient enhanced diffusion in regrown material was merely one-third of the diffusion in original crystalline silicon while the enhanced diffusion in preamorphized silicon had been retarded to 70% of the crystalline silicon value. This shows that a medium germanium implantation dose is sufficient to reduce the depth of the boron doping profile during furnace high-temperature annealing.

Silicon films on sapphire have been implanted with energetic boron and phosphorus ions. The annealing behaviour of the implanted layer, measured by sheet conductivity, has been found to be almost the same as for implantations in bulk silicon.

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The sheet resistivity has been measured in isothermal annealing studies of 10 kohm cm silicon implanted with 40 keV boron ions. The doses used were 2 x 1012 and 2 x 1014 ions/cm2. The annealing was performed in the temperature range 300 to 800°C and the maximum annealing time used was 4 hours at each temperature. The sheet resistivity of the low dose implant at each temperature decreased when the annealing time was increased but the reduction was small during annealing at 550°C. The implant with the dose 2 x 1014 ions/cm2 gave an annealing time dependent increase in the sheet resistivity at the temperature 550°C. The annealing behaviour of the implanted layers seems to be the same for the two doses. Annealing treatment of boron implanted silicon layers give for the two different doses a possibility of varying the sheet resistivity from 60 kΩ/square to 500 Ω/square.

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