作者：Rowlette, PC;Allen, CG;Bromley, OB;Dubetz, AE;Wolden, CA;

作者单位：Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA.;Colorado Sch Mines, Dept Phys, Golden, CO 80401 USA.;Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA.;Colorado Sch Mines, Dept Chem Engn, Golden, CO 80401 USA.;Colorado Sch Mines, Dept Che

刊名：Chemical vapor deposition

ISSN：0948-1907

出版年：2009-01-05

卷：15

期：40911

起页：15

止页：20

分类号：TQ175

语种：英文

关键词：atomic layer deposition (ALD);dimethyl zinc;plasma;zinc oxide;

内容简介

Zinc oxide films are deposited over the temperature range 25-120 degrees C by plasma-enhanced atomic layer deposition (PEALD) using dimethyl zinc (DMZ, Zn(CH3)(2)) as the metal precursor. DMZ is unreactive with molecular oxygen under process conditions, facilitating its utility for PEALD. The deposition rate is independent of plasma exposure (1-5 s) and saturates for DMZ exposures >= 75 mTorr s. The saturated growth per cycle increases from 1.6 to 2.9 angstrom per cycle as the temperature is increased from 25 to 85 degrees C, and remains constant in the range 85-120 degrees C. Over the narrow range explored, substrate temperature has a dramatic impact oil film structure and properties. Polycrystalline films with a (100) texture are obtained at room temperature, with the preferred orientation evolving to the (002) direction as the temperature increases. The electrical resistivity decreases exponentially from 270 at room temperature to values of similar to 5 Omega cm within the ALD window. Compositional analysis shows that films at low temperature are contaminated by carbon and hydroxyl impurities, however these defects are attenuated with temperature and not detected in films deposited within the ALD window. Room temperature photoluminescence is dominated by strong emission from ZnO defects in most films, however these signals are attenuated and strong band edge emission is observed for films deposited at 120 degrees C.