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This work has been done on PECVD2. PECVD2 has been decomissioned but we keep this information because we expect PECVD3 and PECVD4 to behave similar

Boron-doping by use of BSG glass deposited in PECVD2

Results from Joachim Dahl Thomsen, Nanotech, 2014

Recipe

Recipe name	SiH₄ flow [sccm]	N₂O flow [sccm]	N2 flow [sccm]	B₂H₆ flow [sccm]	PH₃ flow [sccm]	Pressure [mTorr]	Power [W]	Description
1PBSG	17	1600	0	120, 130, 140, 160, 240	0	400	380	BSG glass for driving in boron in Silicon

5 tests were made where only the B₂H₆ flow was changed for each deposition (120sccm,130sccm,140sccm,160sccm,240sccm). All deposition times were 2 min, resulting in 440 nm Oxide. The wafers were annealed in Anneal Oxide Furnace (C1) at 1000°C for 85 min to drive in the boron and the oxide was subsequently etched in BHF.

The wafers were then analyzed by SIMS and the results are shown in the figure below:

Boron concentration measured by SIMS. Results from Joachim Dahl Thomsen, Nanotech, 2014.

Boron-doping by use of BSG glass deposited in PECVD2

Results from Trine Holm Christensen, Space, Feb. 2015

Recipe

Recipe name	SiH₄ flow [sccm]	N₂O flow [sccm]	N2 flow [sccm]	B₂H₆ flow [sccm]	PH₃ flow [sccm]	Pressure [mTorr]	Power [W]	Description
1PBSG	17	1600	0	120, 130, 140	0	400	380	BSG glass for driving in boron in Silicon

3 tests were made where only the B₂H₆ flow was changed for each deposition (120sccm,130sccm,140sccm,160sccm,240sccm). All deposition times were 2 min, resulting in approximately 400nm Oxide.

The wafers were going through several annealing and oxidation step:

The total thermal budget for the wafers:

Anneal in Furnace (C1): ANN1000, 30 min in N₂, strip of oxide in a 25 min BHF etch.

Wet oxidation in Furnace (C1): WET1050, 30 min, no further anneal

Anneal in Furnace (C1): ANN950, 60 min in N₂

The wafers were then analyzed by SIMS and the results are shown in the figure below:

Measured peak concentrations and sheet resistances:

Wafer	Peak Concentration [atoms/cm³]	Sheet Resistance [Ω/sq]
BSG120	1.75*10¹⁹	56.4
BSG130	2.44*10¹⁹	36.2
BSG140	2.36*10¹⁹	40.3