Hitachi-high-technologies Corporation

Hisao Nitta

Hisaya Murakoshi

Boklae Cho

Takashi Ichimura

Shigeru Kokubo

Nobuyuki Sonobe

A conventional method to process a tip fails to designate the dimension of the shape of the end of the tip, and so fails to obtain a tip having any desired diameter. Impurities may be attached to the tip. Based on a correlation between the voltage applied or the time during processing of the end of the tip and the diameter of the tip end, the applied voltage is controlled so as to obtain a desired diameter of the tip end for processing of the tip. This allows a sharpened tip made of a tungsten monocrystal thin wire to be manufactured to have any desired diameter in the range of 0.1 &#x3bc;m or more and 2.0 &#x3bc;m or less.

Method for manufacturing electron source

The disclosed charged particle beam apparatus includes a field-emission electron source including &#x3c;310&#x3e; single crystal of tungsten; a vacuum chamber having the electron source therein; an exhausting system for exhausting the vacuum chamber; a filament connected to the electron source to let flow a current through the electron source and thereby heat the electron source; a power supply for letting a current flow through the filament; an ammeter for measuring a total current emitted from the electron source; and a controlling unit for exercising control to cause the power supply to let a current flow through the filament when the total current measured periodically has become a predetermined ratio or less as compared with a total current from the electron source found immediately after first electron beam emission, or a total current from the electron beam found immediately after a current is let flow through the filament.

Growing community of inventors

Tokyo, Japan

Hisao Nitta