Dear Roger.

There are several nice spin -on boron solutions you can se too with much
greater ease than implant or solid disc.
I am sure you wish to avoid wafer damage on the surface and dope about 2.5
ohm per square this is easily obtainable with spin sources form Filmtronics .

They make a PBF solution or Boron A, or B216B that you can spin on and
diffuse for several hours to get this depth, if you wish to do a solid
ceramic disc Planar diffusion which has a diameter of 2 inch 3,4,5,or 6
inch diameter boron which can give you a concentration of 1.4 ohm per
square they have this product too and you can reach 25 microns.
If you can live with a small amount of damage and want to get from 0.10 to
1.5 we can offer another type of diffusion from a preform.

Either Filmtronics can provide a diffusion source and method far less cost
than ion implant ant of excellent quality. I urge you to contact them and
ask for their catalogue. I am sure they can help you as they have helped me.

Sincerely, Neal
At 05:40 PM 12/19/2005 -0800, you wrote:
>I believe most (perhaps all) people driving boron to 25 um do use a furnace
>"pre-deposition".  Boron disks (usually boron-nitride) might be less
>expensive to set up than say, BBr3 or B2O3.  You probably need a dose in the
>range of 5E15 to 1E16 atoms/ cm2.  Watch out for "boron skin" during the
>deposition.  You may need to employ a low temperature "wet" oxidation to
>remove it.