Dear ALL,
    I have some problems with doping boron. I use PECVD silicon di-oxide
(500-600nm) as a diffusion mask. The procedure is that
1) Spin Borofilm 100 on wafer (N-type, 2-5 ohm cm)
2) Diffusion at 1000 degree C for 30min
3) Clean the source, and annealing at 1100 degree C for 2hours.

After these steps, I find there is no pn junction. So I guess it might
be the problem of diffusion mask. Does anyone have experience with that?
The recipe of PECVD SiO2 is:
Ar : 10sccm
O2: 20sccm
MicroWave : 300W
RF power: 0W
Chunk Temperature: 19 degree C
pressure: 20mT

Thanks

HTao