In Situ Study of Live Specimens in an Environmental Scanning Electron Microscope

2013 ◽  
Vol 19 (4) ◽  
pp. 914-918 ◽  
Author(s):  
Eva Tihlaříková ◽  
Vilém Neděla ◽  
Makoto Shiojiri
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Water Layer ◽  
Sample Surface ◽  
Primary Electron ◽  
Environmental Scanning Electron Microscope ◽  
Working Environment ◽  
Environmental Scanning ◽  
Scanning Electron

AbstractIn this paper we introduce new methodology for the observation of living biological samples in an environmental scanning electron microscope (ESEM). The methodology is based on an unconventional initiation procedure for ESEM chamber pumping, free from purge–flood cycles, and on the ability to control thermodynamic processes close to the sample. The gradual and gentle change of the working environment from air to water vapor enables the study of not only living samples in dynamic in situ experiments and their manifestation of life (sample walking) but also its experimentally stimulated physiological reactions. Moreover, Monte Carlo simulations of primary electron beam energy losses in a water layer on the sample surface were studied; consequently, the influence of the water thickness on radiation, temperature, or chemical damage of the sample was considered.

scholarly journals Time Dependent Study of the Positive ion Current in the Environmental Scanning Electron Microscope (ESEM)

2001 ◽  
Vol 7 (S2) ◽  
pp. 788-789
Author(s):  
S.W. Morgan ◽  
M.R. Phillips
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sample Surface ◽  
Primary Electron ◽  
Environmental Scanning Electron Microscope ◽  
Environmental Scanning ◽  
Secondary Electrons ◽  
Positive Ions ◽  
Cascade Amplification ◽  
Scanning Electron

The Environmental Scanning Electron Microscope (ESEM) is capable of image generation in a gaseous environment at sample chamber pressures of up to 20 torr. in an ESEM, low energy secondary electrons emitted from a sample surface, by virtue of the primary electron beam, are accelerated towards the positively biased metallic ring (typically +30 to +550V) Gaseous Secondary Electron Detector (GSED). As these electrons accelerate towards the ring they undergo ionizing collisions with gas molecules producing positive ions and additional electrons known as environmental secondary electrons. The environmental electrons further ionize the gas on their way to the ring producing a cascade amplification of the original signal. The amplified signal induced in the ring is used to form an image. The electric field generated between the GSED ring and the grounded stage causes the positive ions produced in the cascade to drift towards the sample, effectively neutralizing negative charge build up on the surface of a non-conducting sample.

Sign in / Sign up

Export Citation Format

Share Document