Accession Number : ADA622057


Title :   Microstructure of ZnO Thin Films Deposited by High Power Impulse Magnetron Sputtering (Postprint)


Descriptive Note : Interim rept. 29 Jan 2013-16 Feb 2015


Corporate Author : AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE


Personal Author(s) : Reed, A N ; Shamberger, P J ; Hu, J J ; Muratore, C ; Bultman, J E ; Voevodin, A A


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a622057.pdf


Report Date : Mar 2015


Pagination or Media Count : 12


Abstract : High power impulse magnetron sputtering was used to deposit thin (100 nm) zinc oxide (ZnO) films from a ceramic ZnO target onto substrates heated to 150 C. The resulting films had strong crystallinity, highly aligned (002) texture and low surface roughness (root mean square roughness less than 10 nm), as determined by X-ray diffraction, transmission electronmicroscopy, scanning electron microscopy and atomic force spectroscopy measurements. Deposition pressure and target substrate distance had the greatest effect on film microstructure. The degree of alignment in the films was strongly dependent on the gas pressure. Deposition at pressures less than 0.93 Pa resulted in a bimodal distribution of grain sizes. An initial growth layer with preferred orientations (101) and (002) parallel to the interface was observed at the film substrate interface under all conditions examined here; the extent of that competitive region was dependent on growth conditions. Time-resolved current measurements of the target and ion energy distributions, determined using energy resolved mass spectrometry, were correlated to film microstructure in order to investigate the effect of plasma conditions on film nucleation and growth.


Descriptors :   *DEPOSITION , *MICROSTRUCTURE , *SPUTTERING , *THIN FILMS , GRAIN SIZE , LOW TEMPERATURE , NUCLEATION , PRESSURE , SUBSTRATES , SURFACE ROUGHNESS , TEXTURE , ZINC OXIDES


Subject Categories : Physical Chemistry
      Electrical and Electronic Equipment
      Properties of Metals and Alloys
      Fabrication Metallurgy
      Solid State Physics


Distribution Statement : APPROVED FOR PUBLIC RELEASE