Specific Process Knowledge/Doping

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Doping your wafer

This page is about doping your wafer or making a thin film layer doped with boron, phosphorous or Germanium. The links below direct you to various doping results achieved by the use of different processes and heat treatments.


Comparison of different doping processes

Phosphorous predep Boron predep PECVD doped thin film Doped Poly Si Ion implantation
Generel description Dopants introduced by diffusion from gas-phase (POCl3). A thin phosphorous glass is formed on the substrate and phosphorous atoms are driven in. The phosphorous glass is afterward removed by a short BHF etch. Often further annealing is desired in order to redistribute the dopants in the material. This is done at 800°C - 1150°C in either high temperature annealing furnaces or by rapid thermal annealing. Dopants introduced by diffusion from solid source wafers containing B2O3. A boron glass is formed on the substrate and boron atoms are driven in. The boron glass is afterward removed by a low temperature oxidation process (1 hour at 800°C-900°C) in the boron drive in furnace (A1) followed by a BHF etch. Often further annealing is desired in order to redistribute the dopants in the material. This is done at 800°C - 1150°C in either high temperature annealing furnaces or by rapid thermal annealing. Deposition of doped thin film (oxides or nitrides). A high temperature step to drive in and redistribute the dopants in the material is required. This is typically done at 800°C - 1150°C in either high temperature annealing furnaces (C1 or C3) or by rapid thermal annealing. The doped glass can afterwards be removed in a BHF etch. Dopants introduced by in-situ doping of poly/amorphous Si. In some cases you need a high temperature step to redistribute the dopants in the material and alter the crystallinity. This is typically done at 800°C - 1150°C in either high temperature annealing furnaces (C1 or C3) or by rapid thermal annealing. Dopant ions are implanted into the substrate by a high-energy ion beam. Contrary the other doping techniques the doping concentration has a peak inside the substrate when introduced by ion-implantation. Ion implantation cannot be done at Danchip but IBS (Ion Beam Services) offers ion-beam implantation as a service. See more at the homepage of IBS: http://www.ion-beam-services.com/about_us.htm. When wafers return from Ion implantation they need a clean before entering the cleanroom. Activation and redistribution of the dopants is required and is done by a high temperature anneal (600°C-1000°C) in the high temperature furnaces or by rapid thermal anneal.
Process Temperature
  • 900°C - 1150°C
  • 1050°C - 1125°C
  • 300°C
  • 560°C - 620°C
  • Room temperature
Dopant
  • Phosporous (POCl3)
  • Boron (solid source wafers containing B2O3)
  • Phosphorous (PH3)
  • Boron (B2H6)
  • Germanium (GeH4)
  • Phosphorous (PH3)
  • Boron (B2H6 or BCl3)
  • See more information at IBS.
Substrate size
  • 100 mm wafers
  • 50 mm wafers
  • 100 mm wafers
  • 50 mm wafers
  • small samples
  • 50 mm wafers
  • 100 mm wafers
  • 150 mm wafers
  • 100 mm wafers (Boron and Phosphorous)
  • 150 mm wafers (only Boron)
  • See more information at IBS.
Allowed materials
  • Silicon
  • Poly/amorphous silicon
  • Oxide
  • Nitride
  • Silicon
  • Poly/amorphous silicon
  • Oxide
  • Nitride
  • Silicon
  • Poly/amorphous silicon
  • Oxide
  • Nitride
  • Silicon
  • Poly/amorphous silicon
  • Oxide
  • Nitride
  • See more information at IBS.