Transient boron diffusion in medium dose germanium-implanted silicon

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.