semi合集-English.pdf - 第4778页

SEMI C54-1103 © SEMI 2003 8 10.6 Total Hydr ocarbons — This procedure is for the determi nation of tota l hydrocarb ons in oxygen using a continuous fl ow flame ionization detec tor-equipped total hydroca rbon analyzer .…

100%1 / 7923
SEMI C54-1103 © SEMI 2003 7
may not exceed the specification in Section 7 of this
standard.
Sample of
ionConcentrat
Standard of
ionConcentrat
Standard of Absorbance Measured
Sample of Absorbance Measured
=×
10.4 Krypton and Nitrogen — This procedure is for the
determination of krypton and nitrogen using a gas
chromatograph with a thermal conductivity detector.
10.4.1 Detection Limits — 3 ppm krypton, 3 ppm
nitrogen.
10.4.2 Instrument Parameter
10.4.2.1 Column: 3.6 m (12 ft) by 3.2 mm (1/8 in)
stainless steel tubing packed with molecular sieve 5A,
60/80 mesh, washed to remove fines and activated at
300°C for 24 hours or equivalent.
10.4.2.2 Carrier Flow: 45 mL/min helium.
10.4.2.3 Sample Volume: 25 mL.
10.4.2.4 Temperatures:
Detector 40°C
Column 25°C
10.4.3 Calibration Standards — 5–15 ppm krypton, 5–
15 ppm nitrogen, balance helium.
10.4.4 Operating Procedure (Refer to Figure 5)
10.4.4.1 With the valve in Position A, purge the sample
loop with the calibration standard. Switch the valve to
Position B to inject the sample into the column and
allow the oxygen to pass through the column to vent.
Switch valve to Position A to allow the krypton and
nitrogen to be carried to the detector. Record the peak
areas and retention times.
10.4.4.2 Inject the sample to be tested in the same
manner as Section 10.4.4.1. Record the retention times
and peak areas.
10.4.4.3 Repeat 10.4.4.2.
10.4.4.4 Calculate the concentrations of krypton and
nitrogen using the formula below. The result may not
exceed the specification in Section 7 of this standard.
Sample of
ionConcentrat
Standard of
ionConcentrat
AreaPeak Standard
AreaPeak Sample
=×
10.5 Nitrous Oxide — This procedure is for the
determination of nitrous oxide using dual beam optical
non-dispersive infrared spectrophotometry.
10.5.1 Detection Limit — 0.05 ppm.
10.5.2 Instrument Parameters
10.5.2.1 Detector: “Luft” type or equivalent
10.5.2.2 10" Infrared Gas Cell or gas cell with
equivalent sensitivity
10.5.2.3 Sample Cell Pressure: 200 psig for full scale
range 0–5 ppm nitrous oxide or appropriate pressure as
recommended by the cell manufacturer.
10.5.2.4 Sample Flowrate: 500 cc/minute or as
recommended by the instrument manufacturer
10.5.2.5 Wavelength: 4.5 micrometers (4500 nm)
10.5.2.6 Wavenumber: 2222 cm
-1
10.5.3 Calibration Standard: 5 ppm nitrous oxide,
balance oxygen.
10.5.4 Operating Procedure — (See Notes 10, 11 in
Section 10.2.4.) (Refer to Figure 4.)
10.5.4.1 Open the zero gas (prepurified nitrogen or
certified pure oxygen, independently measured to be
less than 0.1 ppm N
2
O) cylinder valve. Open valve V1,
close valves V2 and V3. Flow the gas through the
system and adjust the back pressure regulator to 200
psig as shown on gauge G. Adjust the flowrate on the
flowmeter to 1000 cc/minute by adjusting valve Vl.
After a constant readout is observed, adjust the zero
control knob of the analyzer to set the absorbance
output to read zero.
10.5.4.2 Open the calibration gas standard cylinder
valve. Close Vl and V2, and open valve V3. Flow the
calibration gas through the system and adjust the back
pressure regulator to 200 psig. Adjust the flowrate on
the flowmeter to 1000 cc/minute. After a constant
readout is observed, record the absorbance of the
calibration standard, if the instrument indicates
absorbance directly. If the instrument indicates
concentration, adjust the span control to read the
concentration of nitrous oxide in the calibration gas.
10.5.4.3 Introduce the oxygen sample into the analyzer
by closing valves Vl and V3, opening Valve V4 and
slowly opening valve V2 until the flowrate on the
flowmeter is 1000 cc/minute. Adjust the back pressure
regulator to 200 psig. Read the absorbance of the
sample and calculate the quantity of nitrous oxide,
using the formula below. If the instrument indicates
concentration, record the concentration. The result may
not exceed the specification in Section 7 of this
standard.
Sample of
ionConcentrat
Standard of
ionConcentrat
Standard of Absorbance Measured
Sample of Absorbance Measured
=×
SEMI C54-1103 © SEMI 2003 8
10.6 Total Hydrocarbons — This procedure is for the
determination of total hydrocarbons in oxygen using a
continuous flow flame ionization detector-equipped
total hydrocarbon analyzer. (See Notes 3, 4 in 9.3.)
10.6.1 Detection Limit — 0.1 ppm.
10.6.2 Flow Requirements
10.6.2.1 High purity, hydrocarbon-free (less than 0.1
ppm) hydrogen, 35–40 mL/min or 40% hydrogen in
either helium or nitrogen at 75–80 mL/min.
10.6.2.2 Dry, hydrocarbon-free (less than 0.1 ppm) air,
350 mL–400 mL/min.
10.6.2.3 Set sample flow rate in accordance with the
instrument manufacturer’s instructions.
10.6.3 Calibration Standards
10.6.3.1 Zero oxygen with a known quantity of
hydrocarbons of approximately 0.1 ppm.
10.6.3.2 Upper level balance oxygen span gas of CH
4
that is not more than five times the concentration
specified in Section 7 of this Standard.
10.6.4 Operating Procedure
10.6.4.1 Do not change initial flow settings for
hydrogen, air and sample once established.
10.6.4.2 Introduce the zero oxygen with a known
quantity of hydrocarbons and, using the 0–1 ppm range,
set the output to read the correct level, using the zero
adjust knob.
10.6.4.3 Introduce the span gas standard in oxygen
and, using the span adjust knob, set the output to the
level in the span gas.
10.6.4.4 Introduce the oxygen sample into the analyzer
and read the quantity of hydrocarbons on the analyzer.
The result may not exceed the specification in Section 2
of this standard.
10.7 Water — This procedure is for the determination
of trace moisture (water) in oxygen using a continuous
flowing, cooled-surface condensation, dewpoint/frost-
point hygrometer. (See Notes 5, 6, 7 in Section 9.4.)
10.7.1 Detection Limit — 0.6 ppm at −79°C(−110°F)
10.7.2 Flow Requirements
10.7.2.1 Set sample flow rate and pressure in
accordance with the instrument manufacturer’s
instructions.
10.7.3 Calibration Standard — A calibration ther-
mometer designed to indicate temperatures in the
−79°C (−110°F) range is required.
10.7.4 Operating Procedure
10.7.4.1 An appropriately cleaned stainless steel or
copper sampling line must be used. If it has been
exposed to ambient moisture, it must be purged with
dry gas prior to use.
10.7.4.2 Flow the sample gas through the hygrometer
until the sampling system and instrument have reached
equilibrium with the gas.
10.7.4.3 After equilibrium has been reached, cool the
mirror of the hygrometer, as specified by its
manufacturer, to determine the dewpoint/frostpoint of
the sample gas.
10.7.4.4 Verify the dewpoint/frostpoint reading for at
least 30 minutes after it becomes stable.
10.7.4.5 Correct the dewpoint/frostpoint reading to 1
atm pressure. Convert it to ppm (vol/vol) using an
appropriate table. The result may not exceed the
specification in Section 7 of this standard.
11 Analytical Procedures for Grade 5.8
Oxygen
11.1 Argon and Nitrogen — This procedure is for the
determination of argon and nitrogen in oxygen using a
gas chromatograph with a discharge ionization detector
(see Figure 6).
11.1.1 Detection Limit — 0.1 ppm
11.1.2 Instrument Parameters
11.1.2.1 Column(s):
3 m (10 ft) by 3.2 mm (1/8") o.d. in Molecular Sieve
5A or equivalent.
3 m (10 ft) by 1/8 in Oxy–trap (See Figure 6)
11.1.2.2 Carrier Flow: 44 cc/min
11.1.3 Sample Volume: 0.1 mL
11.1.3.1 Temperatures:
Detector 100°C
Column 30°C
Oxytrap 150°C
11.1.4 Calibration Standards — 1–5 ppm nitrogen and
argon in oxygen.
11.1.5 Operating Procedures
11.1.5.1 Inject the calibration standard into the column
using a gas sampling valve. Record the retention times
and peak area. Order of elution is argon, nitrogen. If
methane is present, the order is argon, nitrogen,
methane.
SEMI C54-1103 © SEMI 2003 9
11.1.5.2 Inject the sample to be tested in same manner
as the calibration standard. Record the retention times
and peak area.
11.1.5.3 Repeat Section 11.1.5.2.
11.1.5.4 Compare the average peak areas of the
calibration standard to that of the sample being tested.
Calculate the concentrations of impurities as shown in
SEMI C3. The result may not exceed the specification
in Section 7 of this standard (see Note 12).
NOTE 12: Oxygen trap conditioned per manufacturer’s
recommendations using hydrogen, carbon monoxide, or blend
in helium.
11.2 Carbon Dioxide — This procedure is for the
determination of carbon dioxide in oxygen using a gas
chromatograph with a flame ionization detector and a
methanizer.
11.2.1 Detection Limit — 0.02 ppm
11.2.2 Instrument Parameters
11.2.3 Column(s): 2.3 m (91 in) by 1/8 in HayeSep Db
11.2.3.1 Carrier Flow: 50 cc/min nitrogen
11.2.3.2 Sample Volume: 5 mL
11.2.3.3 Temperatures:
Detector 275°C
Column 50°C
Methanizer 295°C
11.2.4 Calibration Standards — 0.1–1 ppm carbon
dioxide in oxygen.
11.2.5 Operating Procedures (See Note 13.)
NOTE 13: Sample and calibration sample are injected on
column to vent until oxygen, carbon monoxide, and methane
have eluted. Valve is returned to allow carbon dioxide to elute
onto methanizer and flame ionization detector.
11.2.5.1 Inject the calibration standard into the column
using a gas sampling valve. Record the retention times
and peak area. Order of elution is: Oxygen + carbon
monoxide, methane, carbon dioxide.
11.2.5.2 Inject the sample to be tested in same manner
as the calibration standard. Record the retention times
and peak area.
11.2.5.3 Repeat Section 11.1.10.2.
11.2.5.4 Compare the average peak areas of the
calibration standard to that of the sample being tested.
Calculate the concentrations of impurities as shown in
SEMI C3. The result may not exceed the specification
in Section 7 of this standard (see Note 17).
11.3 Carbon Monoxide and Hydrogen — This
procedure is for the determination of carbon monoxide
and hydrogen in oxygen using a gas chromatograph
with a reduction gas detector.
11.3.1 Detection Limit — 0.002 ppm
11.3.2 Instrument Parameters
11.3.2.1 Column(s): 2 m (80 in) by 1/8 in Molecular
Sieve 13×
11.3.2.2 Carrier Flow: 20 cc/min air
11.3.2.3 Sample Volume: 1 mL
11.3.2.4 Temperatures:
Detector 265°C
Column 105°C
11.3.3 Calibration Standards — 0.5 – 1 ppm hydrogen
and carbon monoxide in nitrogen or oxygen.
11.3.4 Operating Procedures
11.3.4.1 Inject the calibration standard into the column
using a gas sampling valve. Record the retention times
and peak area. Order of elution is: Hydrogen, carbon
monoxide.
11.3.4.2 Inject the sample to be tested in same manner
as the calibration standard. Record the retention times
and peak area.
11.3.4.3 Repeat Section 11.2.4.2.
11.3.4.4 Compare the average peak areas of the
calibration standard to that of the sample being tested.
Calculate the concentrations of impurities as shown in
SEMI C3. The result may not exceed the specification
in Section 7 of this standard.
11.4 Total Hydrocarbons — This procedure is for the
determination of total hydrocarbons in oxygen with a
total hydrocarbon analyzer.
11.4.1 Detection Limit — 0.05 ppm
11.4.2 Instrument Parameters
11.4.2.1 Flow Requirements:
11.4.2.1.1 Carrier Flow Rate: per manufacturer’s
recommendations
11.4.2.1.2 Purity: less than 0.05 ppm total
hydrocarbons
11.4.2.1.3 Sample Flow Rate: manufacturer’s
recommendations
11.4.3 Calibration Standards — 0.1–1 ppm methane in
oxygen.