Title:
ELECTRON BEAM CONTRACTION PROJECTION EXPOSURE DEVICE
Document Type and Number:
Japanese Patent JPS5572031
Kind Code:
A
Abstract:
PURPOSE:To prevent a formed image from poor focussing by a structure wherein a photo-cathode faces a transmittance type mask which is also used as an accelerating electrode, and transmitted electron beam image is contracted and projected. CONSTITUTION:A photo-cathode material 14b is evaporated and uniformly deposited on the glass plate 14a, which is made to face the transmittance type mask 15 installed in the vacuum chamber 9. The mask 15 has a pattern 15a of mesh-type copper thin layer with lines about 1mum wide. The power supply 13 gives the mask 15 a voltage positive against the photo-cathode material 14b. Ultraviolet irradiation on the cathode material 14b causes photoelectrons to be uniformly emitted, which are accelerated by the mask 15 and projected to the projection lens. Even when the photo-cathode 14 is distorted by temperature rise, the structure allows no distorsion of the mask 15, thus permitting transmitting electron beam to maintain its parallelism. The uniformly formed cathode material 14b causes no distortion to the accelerated field and a uniform electron beam shower is projected to the mask 15. Thus, no blurredness occurs to the projected image.
Inventors:
TAKEUCHI YOSHINOBU
UNO TAIDOU
UNO TAIDOU
Application Number:
JP14532878A
Publication Date:
May 30, 1980
Filing Date:
November 27, 1978
Export Citation:
Assignee:
NIPPON TELEGRAPH & TELEPHONE
International Classes:
H01L21/027; H01L21/30; (IPC1-7): H01L21/30