Abstract
Carbon nanotube (CNT) has unique field emission (FE) properties. CNT can emit electrons in lower vacuum condition than other field emitters.
Therefore we have investigated its emission properties and developed a small size scanning electron microscope (SEM) equipped with CNT electron emitter that can operate at low extraction voltages at a pressure of 10-3 Pa.
In order to ensure enough stability for SEM operation, we measured the FE current in various partial pressure condition and numerically analyzed power spectral density function of field emission current by a computer.
As a result, we have found it very effective to heat an emitter and metal parts around an emitter.
Finally, we added heating system in a CNT-FE-SEM and succeeded in taking a stable image.
