HELIUM CHAMBER FOR X RAY EXPOSURE DEVICE

Title:

HELIUM CHAMBER FOR X RAY EXPOSURE DEVICE

Document Type and Number:

Japanese Patent JP01181518

Kind Code:

A

Abstract:

PURPOSE: To enable a high helium concentration to be retained by providing an oxygen monitor for measuring oxygen concentration within an airtight chamber, and a tank for keeping helium gas which is discharged from an airtight chamber.

CONSTITUTION: An oxygen monitor 9 for measuring oxygen concentration within a sealed chamber 5 and a tank 11 with an introduction port which is airtightly connected to the discharge port of an airtight chamber 5 and a discharge port which releases internal gas into air are provided. Then, the oxygen monitor 9 is used to measure oxygen concentration within the airtight room 5 and exposure is performed after confirming that oxygen concentration is fully low. Helium gas discharged from the airtight chamber 5 stays within a tank 11 and helium gas flows into the airtight chamber 5 from the tank 11 even if the airtight chamber 5 is in negative pressure status. It prevents air from flowing into the airtight chamber 5 in reverse direction even if the pressure within the airtight chamber 5 drops due to gas suction by the a pump of the oxygen monitor 9.

Inventors:

Tanaka, Ryoji
Kono, Hidekazu
Iwata, Joji

Application Number:

JP1988000005241

Publication Date:

July 19, 1989

Filing Date:

January 12, 1988

Export Citation:

Click for automatic bibliography generation Help

Assignee:

NEC CORP

International Classes:

G03F7/20; H01L21/027; H01L21/30; (IPC1-7): G03F7/20; H01L21/30

Previous Patent: MANUFACTURE OF SEMICONDUCTOR ELEMENT

Next Patent: ELECTROMAGNETIC WAVE-SHIELDING WALL