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SEMI C54-1103 © SEMI 2003 9 11.1.5.2 Inject the sample to be tested in same manner as the calibration stand ard. Record the retention times and peak area. 11.1.5.3 Repeat Section 11.1.5.2. 11.1.5.4 Compare the average pe…

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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.
SEMI C54-1103 © SEMI 2003 10
11.4.4 Operating Procedures
11.4.4.1 Flow settings should not be changed once
established.
11.4.4.2 Introduce the zero gas and adjust the
instrument per manufacturer’s recommendations to read
the quantity known to be in the zero gas.
11.4.4.3 Introduce the span gas standard and adjust the
instrument per manufacturer’s recommendations to read
the quantity known to be in the span gas. This result
may not exceed specification in Section 7 of this
standard.
11.5 Water — This procedure is for the determination
of trace moisture (water) in O
2
using a continuous
flowing piezoelectric hygrometer (see Note 5, 6, 7 in
Section 9.4).
11.5.1 Detection Limit — 5 ppb
11.5.2 Flow Requirements — Set the sample pressure
and flow rate in accordance with the instrument
manufacturer’s instructions.
11.5.3 Calibration Standards — Construct a
calibration curve that contains at least three points
covering the range of interest. Verify the standards
employed independently by another analytical method.
11.5.4 Operating Procedure
11.5.4.1 Obtain a continuous flow sample of gas from
the source using a clean and passivated stainless steel
line that has been purged dry after exposure to ambient
moisture.
11.5.4.2 After prepurging with a dry gas, allow the
sample gas to flow through the sampling system and the
piezoelectric moisture hygrometer until a stable reading
is obtained.
11.5.4.3 Determine the moisture content of the oxygen
sample by comparing the reading to calibration curve.
The result may not exceed the specification in Section 7
of this standard.