ESEM description

The Philips Electroscan
Environmental Scanning Electron Microscope

Image of the Philips Electroscan ESEM Specialist:
Dr. Stuart McKernan

Description

Equipment

Accessories

Applications

Specifications

Sample Data

Operating Instructions

Description

This scanning electron microscope (SEM) has an ultimate resolution of 5 nm, and an operating chamber pressure range of 10^-5to 20 torr. It operates in air, water vapor, or other gases. Samples do not require coating to be imaged successfully, and the sample temperature may be varied from 20 °C below ambient to 1000 °C. Dynamic experiments may be recorded on a VCR.

Equipment

A differential pumping system allows the entire ESEM® specimen chamber to be maintained at a specific gas pressure. A fully automatic electronic servo system is able to hold this pressure constant between 1 torr and 20 torr. This high pressure is three orders of magnitude higher than the typical SEM and causes no degradation of critical gun or upper column vacuum levels.
The ESEM has a unique secondary electron detector, which is based on the principle of gas ionization and allows imaging of non-conductive samples. Positive ions created in the gas serve to effectively neutralize the destructive build-up of excess electron charge on the specimen.