Effect of Substrate Composition on the Piezoelectric Response of Reactively Sputtered AlN Thin Films;Thin Solid Films

摘要

Effect of substrate composition on the piezoelectric response of reactively sputtered AIN thin films of reactive radio frequency (RF) sputtered AIN thin films. We observed piezoelectric deposition of adjacent thin film layers appeared to have the greatest affect on the value of the piezoelectric response. This suggests that chemical reaction occurring on the Ru thin film the sample is etched, the relatively tall peaks are preferentially etched away until the sample attributed to etching of the AIN film only. In addition, a single thin film of AIN deposited on and the chemically resistant Ru electrode layer was exposed at the surface. That the MN thin The piezoelectric effect of AIN thin films deposited using reactive RF sputtering was layer. Deposition of AIN onto a pristine Ru surface resulted in a piezoelectric response in the negative sense while deposition onto a heavily oxidized Ru surface resulted in a piezoelectric response in the positive sense. Deposition of AIN onto a partially oxidized Ru surface possible to optimize piezoelectric response (magnitude and sign) of AIN thin films by Table I Deposition parameters for Ti// Ru//AlN thin film samples. Table II Presputter/deposition sequence, lag times between Ru and AIN depositions, and piezoelectric responses for AIN//Ru//Ti thin film stacks on oxidized Si. All targets were presputtered prior to deposition of Ti layer resuhing in lag time between presputtering and deposition of all 3 materials. + No lag time between presputter and deposition of thin films. the thin film interfaces and subsequently subtle differences in the thin film deposition products. Presputter/deposition sequences for the constituent thin films in several samples Ru/deposit Ru/presputter AIN/deposit AIN (denoted pTi;TiR.;Ru/pAIN;AIN). TMs led to a lag time between deposition of any two adjacent thin film layers, allowing the underlying was presputter Ti/ presputter Ru/presputter AIN/deposit Ti/deposit Ru/deposit AIN denoted In order to determine the relative dipole orientation within the AIN thin films, etch samples. Sections of the AIN/lRu//Ti//SiOSi/Si wafer samples were etched for times ranging role of the dipole orientation. An additional sample of Ti// Ru was deposited in order to The piezoelectric response for each of the Ti//Ru// AlN samples is shown in Table II thin film layers. For samples in which there was a relatively long lag time (gt; 0.5 hours), the piezoelectric response tended to positive values (e.g. Samples 1,2 and 3). Given our typical pristine surface every five seconds. Exposure of the pristine Ru thin film surface to residual minutes between deposition of the Ru and AIN thin film layers, the piezoelectric response surface affects the dipole orientation of the subsequently deposited AIN thin film which film atomic interactions. Subsequent deposition of the AIN on the oxidized Ru surface