Nano-structured morphological features of pulsed direct current magnetron sputtered Mo films for photovoltaic applications

Abstract

Nano-structured morphological features of pulsed direct current magnetron sputtered Mo films for photovoltaic applications, Thin Solid Films (2011Films ( ), doi: 10.1016Films ( /j.tsf.2011 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Cu(In,Ga)Se 2 based solar cells and as such the properties of these layers play an important role in the overall cell structure. This paper describes the production of molybdenum films using pulsed d.c magnetron sputtering from compressed molybdenum powder targets. The films were deposited at different substrate temperatures under constant power and constant current modes, and analysed using X-ray diffraction, scanning electron microscopy, atomic force microscopy and four point resistance probe. Mechanical strain and resistivity were found to decrease with substrate temperature together with a shift in the (110) crystallographic plane towards higher diffraction angles. All films were well adhered to the glass substrates irrespective of their high tensile strain. Surface morphology analysis revealed the presence of nano-structured stress relief patterns which can enhance the nucleation sites for subsequent CuInSe 2 deposition. A high-resolution cross sectional image showed the columnar growth of the films. Surface roughness analysis revealed that roughness increased with increase in substrate temperature. A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT KeywordsMolybdenum films, Pulsed D.C. Magnetron Sputtering, nano-structured stress relief pattern, powder sputtering, back contact layer.

Properties of MoO3 films by thermal oxidation: Annealing induced phase transition

“…Li et al 35 synthesized Q1D MoO 3 ribbon where the Raman peaks observed at 667 cm −1 , 819 cm −1 and 995 cm −1 are corresponding to the -MoO 3 . 36 37 The similar results were also observed by the Navas et al 25 in MoO 3 films. From Raman studies, it was conclude that, as the annealing temperature increased from 573 to 673 K the mixed phase of MoO 3 converted in to -MoO 3 .…”

“…The as-deposited molybdenum films showed a peak at 2 = 40 3 related to the (110) reflection of metallic Mo with polycrystalline nature. Karthikeyan et al 25 showed similar (110) reflection of molybdenum metal films achieved by pulsed DC magnetron sputtering technique. When the films annealed at 473 K the crystallinity of the metallic molybdenum increased and no reflection observed related to molybdenum oxide.…”

“…Martinez et al 15 reported that the formed at substrate temperature of 673 K exhibits the single phase of -MoO 3 was conformed by X-ray diffraction and Raman studies, and also studied the gas sensing properties. Thin films of molybdenum oxide were formed by different deposition technique like chemical vapour deposition, 16 sol-gel method, 14 Article metal-organic deposition (PMOD), 17 electron beam evaporation, 18 19 Thermal evaporation 20 pulsed laser deposition, 21 and DC [22][23][24][25] and RF sputtering. 4 26-28 Among these techniques, DC magnetron sputtering is widely used to produce the films on large area substrates.…”

Low resistivity molybdenum thin film towards the back contact of dye-sensitized solar cell

“…The diffusion trace of sodium can be controlled by modifying the molybdenum layer thickness, the grain density, and by a diffusion barrier to the glass. 32 Molybdenum can be obtained by pulse direct current magnetron sputtering, 33 thermal evaporation 34 and e-beam evaporation. 35 The DC sputtering is considered a suitable technique for deposition of Mo membrane of which will meet the requirements in solar cell development.…”

Characterization of high quality Cu(In,Ga)Se2 thin films prepared by rf‐magnetron sputtering

“…CIGSbased solar cells have achieved a record efficiency of 20% at the laboratory scale [4]. Recently, scientific and technologic research efforts have been focused on the deposition of CIGS absorbers with low cost single step methods [5,6]. The single step deposition process may cut down the costs of absorber film manufacturing as compared with the complex multi-step processes involved in the traditional deposition techniques.…”