Title :
Fabrication of Cu2ZnSnS4 thin film solar cell using chemical method
Author :
Dhakal, Tara ; Hamasha, Mohammad ; Sunkari, Shwetana ; Ganta, Lakshmikanth ; Vasekar, Parag ; Westgate, Charles
Author_Institution :
Center for Autonomous Solar Power (CASP), State Univ. of New York - Binghamton, Binghamton, NY, USA
Abstract :
We report the growth, characterization and fabrication of the quaternary compound semiconductor Cu2ZnSnS4 (CZTS) thin film solar cell using low temperature chemical synthesis. The constituent materials required for this p-type absorber are earth abundant and available at low cost. In addition, CZTS has large absorption coefficient in the order of 104 cm-1 and has optimum band-gap energy of about 1.5 eV required for an efficient photo-energy conversion. We have adopted a low temperature chemical route followed by spin coating to synthesize CZT layers. Essentially, a metal compound solution of CZT is formed by dissolving Copper (II) acetate, zinc (II) acetate and tin (II) chloride in 2-methoxyethanol and monoethanolamine. The CZT layer, which is formed by spin coating and annealing at around 300°C, is then sulphurized by using a safe organic sulphur source called di-tert-butyl-disulfide (TBDS) for a controlled sulphur transfer at temperature around 400°C to form stoichiometric Cu2ZnSnS4. The Cu to Zn+Sn and Zn to Sn ratios for an optimally synthesized film were 0.87 and 1.2 respectively. Techniques like EDX, XRD and XPS were used for composition, crystallinity and phase analysis.
Keywords :
X-ray chemical analysis; X-ray diffraction; X-ray photoelectron spectra; absorption coefficients; annealing; copper compounds; semiconductor growth; solar cells; spin coating; ternary semiconductors; thin film devices; tin compounds; zinc compounds; 2-methoxyethanol; Cu2ZnSnS4; EDX; XPS; XRD; absorption coefficient; chemical method; constituent materials; controlled sulphur transfer; crystallinity analysis; di-tert-butyl-disulfide; low temperature chemical route; monoethanolamine; optimum band-gap energy; organic sulphur source; phase analysis; photoenergy conversion; quaternary compound semiconductor thin film solar cell fabrication; spin coating; Copper; Films; Photovoltaic cells; Photovoltaic systems; Surface treatment; Tin; Zinc;
Conference_Titel :
Photovoltaic Specialists Conference (PVSC), 2011 37th IEEE
Conference_Location :
Seattle, WA
Print_ISBN :
978-1-4244-9966-3
DOI :
10.1109/PVSC.2011.6186188