A high Q value Y type surface acoustic wave (SAW) mass sensor with apodized interdigital transducer (IDT) and slanting metal array reflectors is reported. P-matrix method was used to analyze the bandpass ripple of three different sensors. The Q value and bandpass ripple of these sensors were compared, respectively, in the active oscillation mode and non-oscillation mode. The reason for obtaining a high Q value was analyzed. Both theoretical and experimental results show that, the side lobe rejection of the sensor with uniformed aperture and no reflector is 10 dB and the Q value is 5 289 under oscillation mode;the side lobe rejection and the Q value are improved to 25 dB and 8 689, respectively by employing the apodization designing; however, both of these two parameters become 25 dB and 12 477, according to the application of the slanting metal array reflectors and the apodized IDT. In non-oscillation mode the bandpass ripple of the sensor with reflectors is about 2 dB lower than that of the sensor without reflectors.Therefore, the application of the apodization IDT and the metal reflector are two important factors to imto Q value improvement.%用P矩阵方法分析带变迹叉指换能器(IDT)和倾斜金属反射栅的高Q值Y型声表面波(SAW)质量沉积传感器的通带纹波,并分别在振荡和非振荡模式下比较了这些传感器的通带纹波和Q值.分析了获得高Q值的原因.理论和实验结果表明:均匀孔径无反射栅的传感器旁瓣抑制为10dB,振荡模式下其Q值为5 289;通过孔径变迹设计,传感器的旁瓣抑制和Q值分别改善到25dB和8689;而对孔径变迹并加入倾斜反射栅的传感器,这两个参数提高到25dB和12477.非振荡模式下带反射栅的传感器比没有反射栅器件的通带纹波约低2dB.因此,变迹IDT和金属反射栅的应用是SAW质量传感器Q值的改善的两个重要因素.由于Q值改善,质量沉积灵敏度达到5.24 GHz·cm2/g
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