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.

• Dope with Phosphorous - Doping Silicon wafers with phosphorous by thermal predeposition and drive-in
• Dope with Boron - Doping Silicon wafers with boron by thermal predeposition and drive-in
• Furnace LPCVD PolySilicon - Deposition of PolySi doped with B or P
• PECVD - Making boron glass (BSG), phosphorus glass (PSG), boron-phosphorous glass PBSG or germanium doped glass
• Ion implantation

Comparison of different doping processes

	Phosphorous predep	Boron predep	PECVD doped thin film	Doped Poly Si
Generel description	Dopants introduced by diffusion from gas-phase (POCL3)	Dopants introduced by diffusion from solid source wafers	Deposition of doped thin film (oxides or nitrides)	Dopants introduced by in-situ doping of poly/amorphous Si
Process Temperature	900°C - 1150°C Removal of the phosphorous glass is done by a short BHF etch. Often further annealing is desired in order to drive in and redistribute the dopants in the material. This is done in either high temperature annealing furnaces or by rapid thermal annealing.	1050°C - 1125°C Removal of the the boron glass is done by a dry oxidation process in the boron drive in furnace (A1) followed by a BHF etch. Often further annealing is desired in order to drive in and redistribute the dopants in the material. This is done in either high temperature annealing furnaces or by rapid thermal annealing.	300°C A high temperature step to drive in and redistribute the dopants in the material is required. This is typically done at 800°C - 1100°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.	560°C - 620°C In most cases you need a high temperature step redistribute the dopants in the material and alter the crystalinity. This is typically done at 800°C - 1100°C in either high temperature annealing furnaces (C1 or C3) or by rapid thermal annealing.
Dopant	Phosporous (POCL3)	Boron (solid source wafers containing B2O3)	Phosphorous (PH3) Boron (B2H6) Germane (GeH4)	Phosphorous (PH3) Boron (B2H6 or BCl3)
Substrate size	100 mm wafers	100 mm wafers	small samples 50 mm wafers 100 mm wafers 150 mm wafers	100 mm wafers (Boron and Phosphorous) 150 mm wafers (only Boron)
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

Ion implantation

Ion implantation cannot be done at Danchip. IBS offers ion-beam implantation as a service. See more at the homepage of IBS: http://www.ion-beam-services.com/about_us.htm