Effects of Deposition Conditions on Properties of AIN Films and Characteristics of AIN-SAW Devices

다양한 증착변수에 따른 AIN 박막의 물성 및 SAW 소자의 특성 분석

  • 정준필 (한양대 전자전기제어계측공학과) ;
  • 이명호 (한양대 전자전기제어계측공학과) ;
  • 이진복 (한양대 전기공학과) ;
  • 박진석 (한양대 전자컴퓨터공학부)
  • Published : 2003.08.01

Abstract

AIN thin films are deposited on Si (100) and $SiO_2$/Si substrates by using an RF magnetron sputtering method and by changing the conditions of deposition variables, such as RF power, $N_2$/Ar flow ratio, and substrate temperature ($T_sub$). For all the deposited AIN films, XRD Peak patterns are monitored to examine the effect of deposition condition on the crystal orientation. Highly (002)-oriented AIN films are obtained at following nominal deposition conditions; RF Power : 350W, $N_2$/Ar ratio = 10/20, T$_{sub}$ : $250^{\circ}C$, and working pressure = 5mTorr, respectively. AIN-based SAW devices are fabricated using a lift-off method by varying the thickness of AIN layer. Insertion losses and side-lobe rejection levels of fabricated SAW devices are extracted from their frequency response characteristics, which are also compared in terms of AIN thickness and substrate. Relationships between the film properties of AIN films and the frequency responses of SAW devices are discussed. It is concluded from the experimental results that the (002)-preferred orientation as well as the surface roughness of AIN film may play a crucial role of determining the device performances of AIN-SAW devices.s.

Keywords

References

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