Setup
  * Pt electrode
    * Can substitute for something more common for RE purposes?
  * 5 % HF or 5 % NH4F
  * Keep 1 - 5 cm between Si and electrode
Procedure
  * Apply positive voltage to Si
Notes
  * Heavier doped areas are removed quicker
  * No oxidizer required (ie light or HNO3)
  * Good at emphasizing various Si doping
  * Much safer than wet chemical alternatives

====== References ====== 
  - http://books.google.com/books?id=9bk3gJeQKBYC&lpg=PA211&ots=7w5HRCwEnF&dq=doping%20etchants&pg=PA211#v=onepage&q=doping%20etchants&f=false