Title :
Spherical φ 1 mm SAW device based on Ball Semiconductor/MEMS technology
Author :
Sim, Dongyoun ; Mizukami, Akio ; Akao, Shingo ; Satoh, Ichitaro ; Bryan, Maxey ; Takeda, Nobuo ; Ohgi, Tuneo ; Nakaso, Noritaka ; Miyagishi, Tetsusya ; Tanaka, Hidekazu ; Fukiura, Ken ; Kazato, Hirohiko ; Watanabe, Hideyuki ; Mihara, Tsuyoshi ; Yamanaka,
Author_Institution :
Ball Semicond. Inc., Allentown, TX, USA
Abstract :
A ball SAW (surface acoustic wave) device was fabricated on a 1 mm φ single crystal quartz sphere. On the z-axis cylinder, it has multiple roundtrips of more than 190 turns and a long propagation length of 157 mm at 150 MHz of driving frequency and 50 turns roundtrip. Using this device, we realized a hydrogen gas sensor as an application of a ball SAW device. Amplitude and delay time responses were measured under exposure to between 10 ppm and 3% H2 in N2 base gas by using a selective sensing film of 40 nm thick Pd/Ni alloy. The response time was about 30 sec in 3% H2.
Keywords :
gas sensors; hydrogen; microsensors; nickel alloys; nitrogen; palladium alloys; surface acoustic wave sensors; 150 MHz; 157 mm; Ball Semiconductor technology; H2; MEMS technology; N2; PdNi; amplitude response; ball SAW device; delay time response; hydrogen gas sensor; palladium-nickel alloy; response time; single crystal quartz sphere; z-axis cylinder; Acoustic propagation; Acoustic waves; Delay effects; Frequency; Gas detectors; Hydrogen; Micromechanical devices; Surface acoustic wave devices; Surface acoustic waves; Thickness measurement;
Conference_Titel :
Ultrasonics Symposium, 2004 IEEE
Print_ISBN :
0-7803-8412-1
DOI :
10.1109/ULTSYM.2004.1417885
