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Title: Growth of residual stress-free ZnO films on SiO{sub 2}/Si substrate at room temperature for MEMS devices

Abstract

ZnO thick Stress relaxed films were deposited by reactive magnetron sputtering on 2”-wafer of SiO{sub 2}/Si at room temperature. The residual stress of ZnO films was measured by measuring the curvature of wafer using laser scanning method and found in the range of 0.18 x 10{sup 9} to 11.28 x 10{sup 9} dyne/cm{sup 2} with compressive in nature. Sputter pressure changes the deposition rates, which strongly affects the residual stress and surface morphologies of ZnO films. The crystalline wurtzite structure of ZnO films were confirmed by X-ray diffraction and a shift in (0002) diffraction peak of ZnO towards lower 2θ angle was observed with increasing the compressive stress in the films. The band gap of ZnO films shows a red shift from ∼3.275 eV to ∼3.23 eV as compressive stress is increased, unlike the stress for III-nitride materials. A relationship between stress and band gap of ZnO was derived and proposed. The stress-free growth of piezoelectric films is very important for functional devices applications.

Authors:
;  [1]; ;  [2]
  1. Sensors & Nanotechnology Group, CSIR-Central Electronics Engineering Research Institute, Pilani, Rajasthan 333031 (India)
  2. Department of Electrical Engineering, Indian Institute of Technology Jodhpur, Jodhpur 342011 (India)
Publication Date:
OSTI Identifier:
22493905
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 6; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CUBIC LATTICES; DEPOSITION; EV RANGE; FILMS; LASER RADIATION; MEMS; MORPHOLOGY; PIEZOELECTRICITY; RED SHIFT; RESIDUAL STRESSES; SILICON; SILICON OXIDES; SPUTTERING; SUBSTRATES; SURFACES; TEMPERATURE RANGE 0273-0400 K; X-RAY DIFFRACTION; ZINC OXIDES

Citation Formats

Singh, Jitendra, Akhtar, Jamil, Ranwa, Sapana, and Kumar, Mahesh, E-mail: mkumar@iitj.ac.in. Growth of residual stress-free ZnO films on SiO{sub 2}/Si substrate at room temperature for MEMS devices. United States: N. p., 2015. Web. doi:10.1063/1.4922911.
Singh, Jitendra, Akhtar, Jamil, Ranwa, Sapana, & Kumar, Mahesh, E-mail: mkumar@iitj.ac.in. Growth of residual stress-free ZnO films on SiO{sub 2}/Si substrate at room temperature for MEMS devices. United States. doi:10.1063/1.4922911.
Singh, Jitendra, Akhtar, Jamil, Ranwa, Sapana, and Kumar, Mahesh, E-mail: mkumar@iitj.ac.in. Mon . "Growth of residual stress-free ZnO films on SiO{sub 2}/Si substrate at room temperature for MEMS devices". United States. doi:10.1063/1.4922911.
@article{osti_22493905,
title = {Growth of residual stress-free ZnO films on SiO{sub 2}/Si substrate at room temperature for MEMS devices},
author = {Singh, Jitendra and Akhtar, Jamil and Ranwa, Sapana and Kumar, Mahesh, E-mail: mkumar@iitj.ac.in},
abstractNote = {ZnO thick Stress relaxed films were deposited by reactive magnetron sputtering on 2”-wafer of SiO{sub 2}/Si at room temperature. The residual stress of ZnO films was measured by measuring the curvature of wafer using laser scanning method and found in the range of 0.18 x 10{sup 9} to 11.28 x 10{sup 9} dyne/cm{sup 2} with compressive in nature. Sputter pressure changes the deposition rates, which strongly affects the residual stress and surface morphologies of ZnO films. The crystalline wurtzite structure of ZnO films were confirmed by X-ray diffraction and a shift in (0002) diffraction peak of ZnO towards lower 2θ angle was observed with increasing the compressive stress in the films. The band gap of ZnO films shows a red shift from ∼3.275 eV to ∼3.23 eV as compressive stress is increased, unlike the stress for III-nitride materials. A relationship between stress and band gap of ZnO was derived and proposed. The stress-free growth of piezoelectric films is very important for functional devices applications.},
doi = {10.1063/1.4922911},
journal = {AIP Advances},
number = 6,
volume = 5,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}
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