Development of A Low Field Ion Extraction System for Time-of-Flight Secondary Ion Mass Spectrometry
10.19756/j.issn.0253-3820.251055
- VernacularTitle:飞行时间二次离子质谱仪中低场离子提取系统的研制
- Author:
De-Ze WANG
1
;
Chen-Xin WU
;
Yi CHEN
;
Fu-Xin DU
;
Lei HUA
;
Hai-Yang LI
;
Jian-Hua WANG
;
Ping CHEN
Author Information
1. 东北大学理学院,沈阳 110000
- Keywords:
Time-of-flight secondary ion mass spectrometry;
Secondary ion extraction system;
Simulation optimization;
Extraction efficiency
- From:
Chinese Journal of Analytical Chemistry
2025;53(7):1072-1081
- CountryChina
- Language:Chinese
-
Abstract:
Time-of-flight secondary ion mass spectrometer(TOF-SIMS)is a highly sensitive surface analysis instrument with high spatial resolution.Traditional TOF-SIMS instruments for sample targets use high field extraction methods.Although the ion collection efficiency is high,it is prone to issues such as low-energy ion beam defocusing,sample morphology sensitivity,and organic molecule ion dissociation.This study aimed to develope an efficient low-field ion extraction system suitable for TOF-SIMS with a continuous beam source.The SIMION simulation software was used to construct a model of the secondary ion optical extraction system.The key factors affecting the extraction efficiency were studied,and the structural parameters of the extraction cone were optimized.Using an indium target as the sample,an experimental test of the performance of the ion extraction system was carried out on the TOF-SIMS instrument.The influences of the voltages of the ion extraction cone and the single lens on the ion extraction efficiency were consistent with the simulation results.By adopting the technology of deflection and coaxial dynamic compensation,the imaging field of view of the ion extraction system was increased to 500 μm×500 μm.The energy window of the ion extraction system reached 10 eV,and the large imaging depth of field of 400 μm was achieved.In the test of a 5 mg/L cholesterol thin film sample,the signal-to-noise ratio of the characteristic peak[M-OH]+reached 4453.The results showed that this low-field secondary ion extraction system effectively improved the performance of the continuous beam TOF-SIMS instrument.
