APS March Meeting 202 Poster

1. Synthesis
Method
PLD
Pulsed Laser Deposition
TO
Thermal Oxidation
ED
Electrodeposition
Grain Size 100 nm 250 µm–6 mm 1 µm
NA 1015 cm-3 1014 cm-3 1018 cm-3
GB Angle Low angle High angle High angle
Charge Carrier Transport in Cu2O: A Puzzle
Garima Aggarwal, Sandeep K. Maurya, and K. R. Balasubramaniam
Department of Energy Science and Engineering, Indian Institute of Technology Bombay, India
• Poor electrical transport
• Conventional scattering centres are not
dominant at operating temperature (RT)
Increasing Grain Size
ND/NA
a 0.08
b 0.05
c 0.04
d 0.02
e 0.01
2 µm
300 µm
(111)
(101)(001)
𝐩 = 𝐍 𝐀𝟏
−
+ 𝐍 𝐀𝟐
−
- 𝐍 𝐃
+
• Two acceptor (VCu and VCu
split
) model is valid
• GBs act as sources/sinks for donor impurities
• High angle GBs affect charge transport at low T
• RT transport is impacted mainly by Cu-split vacancy traps
• The challenge is to minimize trap density or/and neutralize them
• Eg = 2 eV (Direct)
• α = 104 cm-1 (visible)
• Low cost synthesis
GB
Scattering
Trap Assisted
Scattering
EA = 0.24 eV
NA = 3 1015 cm-3
EA = 0.33 eV
NA = 2 1015 cm-3
EA = 0.19 eV
NA = 2 1017 cm-3 µ300 = 0.01 cm2V-1s-1
µ300 = 70 cm2V-1s-1
µ300 = 49 cm2V-1s-1
PLD
TO
ED
1950 2011 2016
Effect of unconventional scattering centres:
• Grain size (GS)
• Grain boundary (GB) type
• Intrinsic defects (EA, NA, ND)
Theoretical
ED TO TO TO TO TO
Characterizations
• SEM, XRD, EBSD
• Temp. dependent Hall measurement (80–300 K)