Influence of Parameters of Quadrupole Mass Spectrometer on Desorption Rate Sensitivity of Thermal Desorption Spectroscopy

In order to assess the relationship between desorption rate sensitivity of thermal desorption spectroscopy(TDS) and parameters of quadruple mass spectrometer(QMS),also determine the optimized characteristics of TDS analysis,a high-sensitivity analysis method using a special deuterium calibration leak on the basis of e second electron multiplier mode of QMS was developed.The effect of parameters of QMS on desorption rate sensitivity was investigated.The results show that operation parameters of QMS affected obviously desorption rate sensitivity of TDS,the ion energy(gate voltage),electron energy,focus voltage,and the range resolution of the QMS should be adjusted to 1 000—1 400 μA,3—3.5 V,50—70 V,-100—-60 V and-5—+5,respectively.So the operating parameters of QMS were also optimized for high-sensitivity analysis of TDS.