PV Absorber Layered Materials Formation Using Potential Pulse Atomic Layer Deposition (PP-ALD),

Tuesday, 30 May 2017
Grand Ballroom (Hilton New Orleans Riverside)
P. W. Sisk (University of Georgia), J. Czerniawski (The University of Georgia), and J. L. Stickney (University of Georgia)
Thin film photovoltaic solar cells are a promising avenue for solar technology. However, they currently are not as cost effective as fossil fuels. Several absorber layer materials have been formed using various methods in the past. CuIn(1-x)GaxSe2(CIGS) is a promising material due to its tunable direct bandgap, allowing thin films to be used in photovoltaic devices.

Previous studies of CIGS done by the author’s group investigated thin film deposition using electrochemical atomic layer deposition (E-ALD). Potential Pulse Atomic Layer Deposition (PP-ALD) is an electrochemical method of atomic layer deposition that relies on alternating cathodic and anodic potential pulses. Cathodic potential pulses long enough to form fractions of a monolayer are used. This is followed by an anodic potential which makes use of the underpotential deposition (UPD) phenomenon to strip away excess bulk, allowing stoichiometric deposits. Because short pulses are used, there is not enough time for excess elemental layers to be formed. PP-ALD is also a one solution co-electrodeposition technique. This differs from the previous E-ALD, which required multiple solution switching, allowing for PP-ALD to have shorter deposition cycles, saving solution and time. Initial results for the formation of In2Se3 and other components of the CIGS compound will be discussed.