[20p-E318-1~13] 【CS.7】 Code-sharing Session of 7.2 & 7.4 & 9.5

△ [20p-E318-10] Development of High Brightness Pulse-TEM Using 120-kV Photocathode Elctron Gun

〇Rina Yokoi¹, Wataru Nagata¹, Takafumi Ishida², Isao Nagaoki³, Toshihide Agemura³, Makoto Kuwahara², Koh Saitoh² (1.Dept. Eng., Nagoya Univ., 2.IMaSS, Nagoya Univ., 3.Hitachi High-Tech. Corp.)

Keywords:photocathode, transmission electron microscope, pulse electron beam

We are developing an electron microscope with a high-voltage DC gun using a semiconductor photocathode. This apparatus is capable of generating a high dynamic range of pulse duration from sub-picosecond to continuation. It is expected to observe high-speed local structural changes. From the beam simulation of pulsed electrons, we could find out the optimum condition of electron gun structure and accelerating electric field considering with the charge density dependence of the brightness and pulse width. Consequently, we found that it is possible to realize 4 × 10¹⁰-A cm^-2 sr^-1 peak brightness, 1.1-ps pulse width and 300-aC/pulse charge density at 120-kV acceleration voltage and 1-ps laser pulse width. Furthermore, we succeeded in generating electron beam synchronized with a driving laser and preparing to measure the brightness.