Applied Surface Science, Vol.254, No.9, 2638-2641, 2008
PLD of X7R for thin film capacitors
Thin film capacitors with a thickness of 200 nm were prepared on SrTiO3 ( 1 0 0), ( 1 1 0) and ( 1 1 1) single crystal substrates at a temperature of 973 K by pulsed laser deposition ( PLD) using a KrF excimer laser in an O-2 - O-3 atmosphere with a gas pressure of 1 Pa using an X7R sintered target. As a result, perovskite BaTiO3 solid solution films were obtained. In the X7R thin films on ( 1 0 0) and ( 1 1 0) SrTiO3, only diffraction peaks with strong intensities from BaTiO3 ( 1 0 0) and ( 1 1 0), respectively, were observed. X7R films on SrTiO3 ( 1 1 1) were grown epitaxially oriented to the crystal plane direction of the substrate by inserting an initial homoepitaxial SrTiO3 layer with a thickness of 4 nm. The X7R/SrTiO3 film capacitors yielded a large volumetric efficiency of 50 mu F/mm(3) and a temperature coefficient of capacitance (TCC) of - 1.3% to 1.3% which satisfies the EIA standard specifications for X7R. (C) 2007 Elsevier B. V. All rights reserved.