Alternate Energy Materials & Systems

Worked on research & development of metallized polypropylene film based AC capacitors.• Primary duties included conducting basic research on film capacitors, involving design & development, complete characterization, developing test methods/fixtures, and conducting failure analysis.• Handled global strategic development projects of the company related to new product development and improvement of existing technology in AC film capacitors.

Worked on development of CIGS thin film solar cells for off-grid applications. Job responsibilities included formulating experimental plans for process optimization, device integration and characterization; carrying out different processing steps for fabricating lab scale CIGS devices; and performing structural/electrical/optical characterization of different layers used CIGS device structure.• Assisted in establishing and smooth functioning of a state of the art thin film characterization facility at MBIL. Equipped with instruments like SEM/EDS, XRD, XRF, Van der Pauw/Hall measurement, UV-VIS/NIR spectrometer, solar cell I-V tester, etc., this facility is able to fulfill most of the measurement and characterization needs of various R&D functions of MBIL.• Devised an alternate methodology for determining residual stress in thin films using X-ray diffraction. This method (based on the popular sin2-psi technique) allowed reliable stress measurements to be made without tilting or rotating the specimen inside XRD. • Carried out a detailed stress analysis on sputtered Mo layers, which helped in optimizing the sputtering process to obtain excellent quality Mo back contacts (resistivity < 20 Ω-cm, residual stress < 150 MPa with good adhesion on SLG substrates) for our CIGS devices.• Optimized the sputtering of Cu/In/Ga precursor and rapid thermal annealing based selenization process to improve structural and compositional qualities CIGS absorber layer.• Optimized ZnO:Al layer deposition by RF sputtering to meet strict process requirements of CIGS devices. Achieved properties (resistivity ~6e-4 Ω-cm and avg. visible transmittance > 86%) are among the best reported for ZnO:Al films deposited on unheated substrates and without any post-deposition treatment.

Mentored two research scholars in their experimental work. The work focused on two different types of electrical contacts: 1) Sliding electrical contacts for low power device and control applications; and 2) Stationary metal contacts at cryogenic temperatures for space related applications. A part of the same work was later presented in 57th IEEE Holm Conference (June 2011) on Electrical contacts, held in Minneapolis, USA.

Worked on a consultancy project involving specific contact resistance studies on corroded chromium plated aluminum panels for generator applications.