High rate amorphous and crystalline silicon formation by pulsed DC magnetron sputtering deposition for photovoltaics

Abstract

Two methods of pulsed DC magnetron sputtering deposition have been used to form high rate, hydrogen‐free crystalline silicon layers. The first method is in situ crystalline silicon deposition. The second method is high rate amorphous silicon deposition followed by an anneal to induce crystallization. Over 20 μm thick crystalline silicon can be formed on wafers up to 200 mm round or 156 mm square. Two vacuum deposition systems were used for substrate cleaning and deposition. The crystallinity of silicon layers was analyzed by ellipsometry and Raman spectroscopy. Almost fully crystalline silicon is deposited in situ at table temperatures greater and equal to 650 °C. In situ crystalline silicon has been deposited at 40 nm/min and amorphous silicon can be deposited at over 400 nm/min subject to power density limitations for the silicon target. Up to 20 μm thick amorphous silicon deposited at room temperature is fully crystallized by annealing in vacuum on a 1000 °C table for 2 h. This work demonstrates that sputtering offers significant potential for depositing the absorber layer in silicon based photovoltaics.

Wet chemically prepared silicon nanowire arrays on low‐cost substrates for photovoltaic applications

“…The samples used in this work were: (A) thin mc‐Si films deposited on glass substrates, prepared by the layered laser crystallization (LLC) process 16 (total thickness of the mc‐Si 1.88 µm), (B) EFG wafers (moderately n‐doped), (C) mc‐Si wafers produced from MG‐Si (highly doped p + (∼10 19 cm −3 )), (D) 2 µm thick a‐Si magnetron sputter deposited 17 onto mc‐Si produced from MG‐Si and subsequently crystallized in furnace at 600 °C under N 2 flow for 16 h.…”

Light absorption enhancement in ultrathin film solar cell with embedded dielectric nanowires

“…Such a layer is then annealed in vacuum at a temperature of 1000 °C for crystallization as shown in Fig. 8b [21][22][23][24][25][26] . Figure 8c shows the deposition of the second silicon layer with a thickness of 236 nm on p-type silicon and Si 3 N 4 layer at a temperature of 690 °C.…”

“…Figure 8 c shows the deposition of the second silicon layer with a thickness of 236 nm on p-type silicon and Si 3 N 4 layer at a temperature of 690 °C. The substrate is annealed in vacuum at 1000 °C for 30 min to achieve fully crystalline silicon film 23 . Next, photolithography process is used to make an isotropic etching of the required cleavages to anchor the first layer of NWs 27 .…”

“…A layer of Si with thickness of 464 nm is next deposited using argon gas and is annealed in vacuum at 1000 °C for 30 min 23 . Additionally, n-thin layer of silicon is deposited with a thickness of 100 nm at 1000 °C using dichlorosilane (DCS), and phosphine (PH 3 ) as N-dopants with doping concentration of 1 × 10 19 cm −3 22 .…”

Growth and Characterization of Polycrystalline Silicon Thin Films for Photocatalytic Splitting of Water in Oxide-Si Tandem Cells

“…In a very recent work by Louise R. Bailey et.al. [31] pulsed DC magnetron sputtering was used to deposit hydrogen free Si films on a glass substrate. Characterization of these films was carried out using micro-Raman spectroscopy and showed a large crystalline fraction for annealing in a vacuum tube at 1000P o P C for 2 hours.…”