%0 Journal Article
%K Sputtering
%K Lithium nickel oxide
%K Pulsed laser deposition
%A Michael D Rubin
%A Shi-Jie Wen
%A Thomas J Richardson
%A John B Kerr
%A Klaus von Rottkay
%A Jonathan L Slack
%B Solar Energy Materials and Solar Cells
%D 1998
%G eng
%N 1-4
%P 59-66
%R 10.1016/S0927-0248(97)00223-7
%T Electrochromic lithium nickel oxide by pulsed laser deposition and sputtering
%V 54
%1 <p>Windows and Daylighting Group</p>
%2 LBNL-39411
%8 07/1998
%X <p>Thin films of lithium nickel oxide were deposited by sputtering and pulsed laser deposition (PLD) from targets of pressed LiNiO<sub>2</sub> powder. The composition and structure of these films were analyzed using a variety of techniques, such as nuclear-reaction analysis, Rutherford backscattering spectrometry (RBS), X-ray diffraction, infrared spectroscopy, and atomic-force microscopy. Crystalline structure, surface morphology and chemical composition of Li<sub><em>x</em></sub>Ni<sub>1−<em>x</em></sub>O thin films depend strongly on deposition oxygen pressure, temperature as well as substrate–target distance. The films produced at temperatures lower than 600°C spontaneously absorb CO<sub>2</sub> and H<sub>2</sub>O at their surface once they are exposed to the air. The films deposited at 600°C proved to be stable in air over a long period. Even at room temperature the PLD films are denser and more stable than sputtered films. RBS determined the composition of the best films to be Li<sub>0.5</sub>Ni<sub>0.5</sub>O deposited by PLD at 60&nbsp;mTorr O<sub>2</sub> pressure. Electrochemical tests show that the films exhibit excellent reversibility in the range 1.0–3.4&nbsp;V versus lithium. Electrochemical formatting which is used to develop electrochromism in other films is not needed for the stoichiometric films. The optical transmission range is almost 70% at 550&nbsp;nm for 150&nbsp;nm-thick films. Devices made from these films were analyzed using novel reference electrodes and by disassembling after cycling.</p>