???_??_??

?? (Vacuum)
??? ???? ????
1?? : ?????? ???? ????
????? ??? ???? ??
?? ?? = 1.013X105 N/m2 = 10130 Pascal = 101.3hpascal= 1013mbar
??? ??? ?? ? ??? ?? ??
1??? ???? ???? ???
(? ?? = 1 g/cc = 103kg/m3 )
1ATM = ¦Ñ g h = (103kg/m3 )(9.8m/s2)h
= 1.013 x 105 Pascal
1??? ???? ????????
Hg(??) ? ??? ?? ? 13?
1??? ??? ??? ?? = 760mm
1?? = 760mmHg = 760 Torr
1micron = 1micrometer Hg =1/1000 torr
??? ?
?????? 13pd ?? ???? ?????
(???)
?????? ??? ? 700 Torr
?, ???? ???? ? ??!!
13pd
¨P6kg
1??
1??
P??
??
100cm2
??? ??
Mean free path (¦Ë)
?? ???? ???? ??
Ex) 1 mTorr ? ?? ¦Ë¨P5cm
10-5 Torr ? ?? ¦Ë¨P5mm
??? ??

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MFC
10sccm
Pumping
Chamber
base pressure
Ar gas
2. Use MFC
MFC
0sccm
Pumping
Chamber
base pressure
Ar gas
Conductance Formulae
1. In the viscous flow region
D : diameter , L : length of the tube (cm)
2. In the molecular-flow region
Independent of pressure
of tube of circular cross section (air at 20¡æ)
Useful for determining the dimesnions of roughing and forepump lines.
Useful in determining the dimesnions of a high-vacuum chamber and the size of the tube leading from the chamber to a high-vacuum pump.
ulations
Valves
of Throttle Valves
23
24
?????: ??? ??? ? ?? ?? ???? ???? ???? ????? ????? ??? ?? ????? ??? ? ??.
25
????? : ?? ????? ??? ? ?? ????, ??? ??? ?? ?? ????? ??? ?? ????? ?? ?? ????.