- Simple, no complex equipment needed.
- Startup is low cost.
- No reactivation cycles like Boron
- Exhibit a minimum of water absorption
- Can be removed from diffusion boats.
This results in long quartz ware life.
- Extended time between tube deglaze
operations, thus reducing furnace down time.
- Controlled dopant release reduces
- Any carrier gas can be used: nitrogen,
- Oxygen insensitive. Deposition process
can be optimized for best electrical results.
- Uniform and clean deposition, regardless
of wafer size.
- Technical support by FAB experienced
- Comparable costs to other solid sources,
like boron nitride.
- Long use life.
- During use, dimensional size remains
the same due to its structural ceramic matrix.
- Safe and easy to use. No health issue
with handling of the sources.
- High wafer load capacity, whole tube
can be used.
- Gases are less expensive, but this
is offset by the cost savings of the other positives of
BBr3 (boron tribromide), Pockle or Phosphorous
Oxytrichloride (POCl3), Boron Trimethyl (B(CH3)3),
Boron Trichloride (BCL3)3), and Phosphine
- Pure depositions
- Material costs are low.
- Glazing of furnace tube increases equipment
- Non-uniform deposition, which increasing
problems with larger wafer size.
- Gases required are toxic and problematic
for health issues.
- Gases required are corrosive.
- Support and maintenance costs
are higher due to the health and equipment requirements
needed for the toxic and corrosive gases required.
- Typically wafer load size is small,
for good dopant uniform.
- Simple application, use of coating
- Can have high surface damage
- Very sensitive to trace impurities
- Startup cost involves specialized
Diborane (B2H6), Boron Trifluoride (BF3)
- Uniform doping
- Safe during implantation use.
- Dangerous gases must be used for implantation,
health and safety requirements.
- Startup cost is very capital intensive.
- High maintenance cost, part costs,
and down time.
- Implantation has silicon channeling
which can negatively impact electrical performance and final
- Silicon damage results from the implantation
and additional processing is needed for annealing this damage.
Boron Nitride Solid Sources
- Uniform doping
- Simple to use.
- Impurities are deposited
- Sources are very hygroscopic (absorbs
moisture quickly). This causes resistivity consistency issues.
- High silicon damage occurs due to high
- Users observe source warpage during
- Sources thin during use. This
causes deposition uniformity problems as they lean in the
boat during use.