Hello everybody,

I recently tried to lighly diffused silicon by Boron. The expected
concentration is around 5e17 atoms/cm3. I reduced the temperature to 800C,
and pre-diffused in 15 minutes. For drive-in, I made at 1100C/30minutes. I
estimated the concentration should be 1e18 atoms/cm3 by Frick's law.
However, after the process, I can not measure the sheet resistance of doped
wafer.
The based concentration of the n-type wafer is 1e17 atoms/cm3, and I doped
it succesfully with the prediffusion temperature of 1000C.
Is boron solubility a problem, or the based concentration too high?
By the way, I can not dope the silicon by ion implantation method here. I
really appreciate any ideas or suggestions.
Best regards


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Dau Thanh Van
Ritsumeikan Uni.
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