Growth of Cu2S/CdS nano-layered photovoltaic junctions for solar cell applications

Layered Cu2S/CdS photovoltaic p–n junctions were fabricated via a simple and reproducible route. CdS inner layer was grown on ITO substrate using chemical bath deposition process for different times. The utilized bath consisted of cadmium sulfate and thiourea with concentrations of 0.05 M and 0.07 M, respectively. CdS layer grown for 600 min was uniform with a thickness of about 500 nm. Moreover, band gap energy of the CdS inner layers was measured as 2.40–2.44 eV depending on the thickness of the layer. Cu2S outer layer was formed over the CdS via ion exchange chemical route, in a bath consisting of copper chloride aqueous solution. EDS, XRD, and XPS were utilized to characterize the formation of cadmium sulfide, and copper sulfide phases during the fabrication steps of the p–n junctions. Nano-layered cell, each layer 200–250 nm in thickness was fabricated with an apparent band gap of 2.22 eV. SEM imaging of both inner and the outer layers confirmed the uniformity and homogeneity of the CdS and the Cu2S layers.

[1]  D. R. Johnson,et al.  Microstructure of electrodeposited CdS/CdTe cells , 2000 .

[2]  W. Jaegermann,et al.  Interface properties and band alignment of Cu2S/CdS thin film solar cells , 2003 .

[3]  P. Cowache,et al.  Electroplating of CuxS on CdS , 1984 .

[4]  Ashutosh Kumar Singh,et al.  Effect of complexing agent on the photoelectrochemical properties of bath deposited CdS thin films , 2010 .

[5]  J. Bernède,et al.  ZnO thin films fabricated by chemical bath deposition, used as buffer layer in organic solar cells , 2009 .

[6]  C. Harland Ion exchange : theory and practice , 1994 .

[7]  Hao Wang,et al.  Synthesis of CuS thin films by microwave assisted chemical bath deposition , 2009 .

[8]  E. Eser Junction geometry in Cu2S/CdS or Cu2S/Cd1−xZnxS solar cells prepared by the solution reaction method , 1983 .

[9]  P. K. Nair Semiconductor thin films by chemical bath deposition for solar energy related applications , 1998 .

[10]  A. M. Chaparro,et al.  Photovoltaic windows by chemical bath deposition , 2000 .

[11]  D. Fornasiero,et al.  The evolution of surface layers formed during chalcopyrite leaching , 2006 .

[12]  R. Esen,et al.  Annealing studies on CBD grown CdS thin films , 2003 .

[13]  K. Durose,et al.  Development of low temperature approaches to device quality CdS: A modified geometry for solution growth of thin films and their characterisation , 2007 .

[14]  K. Y. Rajpure,et al.  Room temperature synthesis and characterization of CdO nanowires by chemical bath deposition (CBD) method , 2008 .

[15]  Qingwei Li,et al.  Controllable growth of well-aligned ZnO nanorod arrays by low-temperature wet chemical bath deposition method , 2010 .

[16]  C. Lokhande,et al.  Chemically deposited nanocrystalline NiO thin films for supercapacitor application , 2008 .

[17]  R. Esen,et al.  Effects of deposition time and temperature on the optical properties of air-annealed chemical bath deposited CdS films , 2006 .

[18]  H. Uda,et al.  Thin CdS films prepared by metalorganic chemical vapor deposition , 2003 .

[19]  T. Shripathi,et al.  Quenching of photoconductivity in Fe doped CdS thin films prepared by spray pyrolysis technique , 2008 .

[20]  Jae-Hyeong Lee Influence of substrates on the structural and optical properties of chemically deposited CdS films , 2007 .

[21]  V. M. Nikale,et al.  Substrate dependent properties of electrodeposited EuTe thin films , 2003 .

[22]  Mohd Zobir Hussein,et al.  Cathodic electrodeposition of Cu2S thin film for solar energy conversion , 2002 .

[23]  D. Amalnerkar Photoconducting and allied properties of CdS thick films , 1999 .

[24]  Sanghoo Park,et al.  Characterization of gallium-doped CdS thin films grown by chemical bath deposition , 2009 .