semi合集-English.pdf - 第3890页

SEMI F27-0997 © SEMI 1997, 2003 5 Regulators should be tested in the fully-open cond ition (i.e., with the regulator adjus ted for minim u m pressure drop). The quantity o f published data on regulator interaction with m…

SEMI F27-0997 © SEMI 1997, 2003 4

7.1.1 Initial Dry Down — Start the experiment with the

blank in place of the test specimen and a flow of dry

gas through the APIMS. The APIMS output should be

at equilibrium with the lowest moisture level of interest,

and in any case no higher than 500 ppt. The flow rate

through the test blank should be set according to the

Flow Table (see Table 1).

7.1.1.1 Switch the gas flow to pass primarily through

the bypass loop while maintaining a small flow through

the test blank. Remove the test blank completely from

the system. If a glove box or other such enclosure is

used, do not remove the test blank from the glove box.

Immediately reconnect the test blank to V

, leaving it

disconnected from V

. Allow dry nitrogen to flow

through the test blank for five minutes to purge the air

from inside before reconnecting to V

. Switch the gas to

flow only through the blank and not through the bypass

loop. The APIMS will show an increase in moisture

concentration. Record the APIMS output until it

reaches 500 ppt or for 24 hours, whichever is less.

7.1.1.2 Repeat the above test twice for a total of three

data sets.

7.1.2 Moisture Input Test — After the APIMS has

returned to equilibrium with its initial moisture level,

switch the input gas to 50 ppb moisture (by switching

valves V

, V

, and V

simultaneously, if the

arrangement of Figure 1 is used) while recording the

APIMS response. Maintain this moisture input for 20

minutes. Switch the input to the test blank back to dry

nitrogen and record the decease in moisture level until

the initial background is again reached.

7.1.2.1 Repeat the above test twice for a total of three

data sets.

7.2 Tests on Actual Specimen

7.2.1 Initial Dry Down — This portion of the test is

designed to determine the quantity of removable

moisture on the wetted surfaces of a component in the

condition in which it is typically supplied. Thus, the

results of this test will reflect, by design, any

precautions which the supplier has taken to remove

moisture and maintain its dryness during shipping.

7.2.1.1 Start the test as in Section 7.1.1. The test

specimen should not be unpacked until after the APIMS

has equilibrated with the background moisture level. If

a glove box or other such enclosure is used, unpack the

component in the glove box. Switch the dry nitrogen

flow to pass through the bypass loop while maintaining

a small component through the test blank. Undo the

final layer of packing and any shipping caps or plugs on

the component at this point. Remove the sample blank

and connect the test specimen to valve V

as quickly as

possible. Allow the dry nitrogen flow to purge out any

ambient air in the specimen for five minutes, then

connect the specimen to V

. Switch the gas to flow only

through the test specimen and not through the bypass

loop. The APIMS will show an increase in moisture

concentration. Record the APIMS output until it

reaches 500 ppt or for 24 hours, whichever is less.

7.2.1.2 After 24 hours, the dry-down part of the test

can be terminated. If necessary, the moisture level can

be reduced below 500 ppt by baking the component at

200°C or the maximum temperature allowed by the

manufacturer for six hours and/or purging at the highest

flow of dry gas available. If this is not sufficient to

reduce the moisture concentration below 500 ppt, the

test may be abandoned.

7.2.2 Moisture Input Test — After the APIMS has

returned to equilibrium with its initial moisture level,

switch the input gas to 50 ppb moisture (by switching

valves V

, V

, and V

simultaneously, if the

arrangement of Figure 1 is used) while recording the

APIMS response. Maintain this moisture input for 20

minutes. Switch the input to the test blank back to dry

nitrogen and record the decease in moisture level until

the initial background is again reached.

7.2.2.1 Repeat the above test twice for a total of three

data sets.

7.2.2.2 In case the moisture level recorded by the

APIMS does not reach 50 ppb within 20 minutes, an

additional test should be performed in which the

moisture input should be continued until equilibrium is

reached. Then switch the input to the test specimen

back to dry nitrogen and record the decease in moisture

level until the initial background is again reached.

This test should be repeated once (two data sets total).

7.2.3 Bake-Out Test — Heat component to maximum

bake temperature, according to manufacturer’s

specifications, for three hours. Allow it to return to

room temperature. Continue by repeating the moisture

input test, after baking, as in Section 7.2.2.

7.3 Temperature, Flow Rate, and Pressure

Specification — The recommended test pressure is 700

kPa (7 bar). However, lower test pressures are

appropriate for some models of APIMS. Also, the

maximum pressure rating of the test components should

not be exceeded. The component temperature shall be

maintained at 35 ± 1°C during the test.

7.3.1 In the case of tubing, the test shall be carried out

at a single flow determined by the tubing diameter

according to the following table. In the case of valves,

regulators, mass flow controllers (MFC’s), and passive

components (gauges, flow meters, and fittings), the test

will be carried out at a single flow determined by the

table according to the size of the connecting tube stubs.

SEMI F27-0997 © SEMI 1997, 2003 5

Regulators should be tested in the fully-open condition

(i.e., with the regulator adjusted for minimum pressure

drop). The quantity of published data on regulator

interaction with moisture is limited, and experiments to

investigate the effect of varying the pressure drop

across the regulator are encouraged but are not part of

this test. MFC’s should be tested with a flow control

device upstream and the MFC not actively controlling

the flow through it (usually referred to as the “purge”

setting). It may not be possible to test a given MFC at

the specified flow if the flow rating of the MFC is much

less than the specified flow. As MFC’s are not expected

to vary greatly in performance according to their flow

rating, MFC’s to be tested should generally be chosen

to be compatible with the table. If this is not possible,

then the MFC should be tested at its rated flow (lower

than the flow in the table). This can then be considered

a conservative test, as the MFC operated at higher flow

would be expected to dry down more quickly.

7.3.2 Particle filters with the same size tubing

connectors often have somewhat different sizes and

very different flow ratings. In order to be able to make

reasonable comparisons between the performance of

different filters, it is essential to test filters of similiar

size at the same flow. However, the flow dependence of

the moisture response of particle filters is more

complex than that of tubing, and they must be tested at

more than one flow in order to model their behavior. In

order to meet this requirement and provide data which

can be readily compared with the conditions under

which the filters can be expected to be used in practice,

filters shall be tested at two flows: The first, according

to the size of the connecting tube stubs, the second, to

be 25% of the rated flow of the filter or 50 slm,

whichever is less.

7.3.3 For systems of components, the system shall be

tested at the lowest flow of those determined for each

component in the system considered separately. If the

system includes a filter, it shall be tested at that flow

and additionally, at 25% of the rated flow of the filter or

50 slm, whichever is less.

Table 1 Flow Rate

Tubing Outer Diameter

(nominal)

Flow (all

components)

Flow for Second

Test on Filters

≥ 1/8", < 1/2"

(≥ 3.2 mm, < 12.7 mm)

6 slm

≥ 1/2"

(≥ 12.7 mm)

13 slm

25% of rated flow

or 50 slm

whichever is less

8 Reporting Results

8.1 Complete moisture response curves for all test

specimens and relevant test blanks should be included.

A summary sheet may compare components in terms of

“induction time,” peak height, and/or decay time.

Temperature, pressure, and flow measurements, and as

complete a record as possible of all experimental

variables should be noted.

NOTICE: SEMI makes no warranties or

representations as to the suitability of the standards set

forth herein for any particular application. The

determination of the suitability of the standard is solely

the responsibility of the user. Users are cautioned to

refer to manufacturer’s instructions, product labels,

product data sheets, and other relevant literature

respecting any materials mentioned herein. These

standards are subject to change without notice.

The user’s attention is called to the possibility that

compliance with this standard may require use of

copyrighted material or of an invention covered by

patent rights. By publication of this standard, SEMI

takes no position respecting the validity of any patent

rights or copyrights asserted in connection with any

item mentioned in this standard. Users of this standard

are expressly advised that determination of any such

patent rights or copyrights, and the risk of infringement

of such rights, are entirely their own responsibility.

International), 3081 Zanker Road, San Jose, CA 95134. Reproduction o

the contents in whole or in part is forbidden without express written

consent of SEMI.

SEMI F28-1103

TEST METHOD FOR MEASURING PARTICLE GENERATION FROM

PROCESS PANELS

This test method was technically approved by the Global GasesCommittee and is the direct responsibility of

the North American Gases Committee. Current edition approved by the North American Regional Standards

Committee on September 25, 2003. Initially available at www.semi.org October 2003; to be published

November 2003. Originally published September 1997.

1 Purpose

1.1 The purpose of this document is to define a method

for testing process panels intended for installation in

high-purity gas distribution systems. Application of this

test method is expected to yield comparable data among

process panels tested for the purposes of qualification

for this installation.

1.2 This document describes a test method designed to

draw comparisons of particulate generation

performance of process panels. This test method

evaluates the cleanliness of process panels in the “as

received” condition as well as under normal operating

conditions. The “as received” test is intended to enable

the user to evaluate the fabrication, cleaning, and

packaging techniques of the manufacturer of the

process panel. The test under actual operating

conditions is intended to allow the user to evaluate the

manufacturer’s component selection as well as the

quality of the panel design. The specific flow rates

described in both test methods are representative of

relatively high flow conditions for a typical process

panel.

2 Scope

2.1 This test method addresses total particle counts

greater than the minimum detection limit (MDL) of the

particle counter and does not consider classifying data

into various size ranges.

2.2 This procedure utilizes a particle counter applied to

process panels typically used in semiconductor

applications. It applies to process gas supply systems

(e.g., gas cabinets) which include a process panel, an

inert purge panel, and a system vent. Both automatic

and manual process panels are within the scope of this

test procedure. Panels, as defined in this test method,

are considered to consist of 6.35 mm O. D. × 0.89 mm

wall (1/4" O.D. × 0.035" wall) tubing and components.

NOTICE: This standard does not purport to address

safety issues, if any, associated with its use. It is the

responsibility of the users of this standard to establish

appropriate safety and health practices and determine

the applicability of regulatory or other limitations prior

to use.

3 Limitations

3.1 This test method specifies flow and mechanical

stress conditions considered typical of conditions which

would be expected under moderately aggressive

operating conditions. These conditions should not

exceed those recommended by the manufacturer.

Actual performance under operating conditions at lower

flow rates or less aggressive conditions may differ. This

test method does not address particle generation under

vibrating conditions.

3.2 The test medium is limited to nitrogen, argon, or

clean dry air (CDA). Performance with other gases may

differ.

3.3 The accuracy of the data generated by this method

is limited to the accuracy of the particle measuring

instruments utilized.

3.4 This method is written with the assumption that the

operator understands the use of the apparatus at a level

equivalent to six months of experience.

3.5 This document is not intended as a methodology

for monitoring on-going particulate performance once a

particular process panel has been tested. Also, this

method does not include extended dynamic particle

count testing (particle generation after thousands of

cycles).

3.6 Auto-crossover systems are not within the scope of

this test procedure.

NOTE 1: It should be mentioned that test results from panels

equipped with final outlet filters can differ significantly from

test results from panels without filters.

4 Referenced Standards

4.1 ISO Standards

ISO 14644-1 — Cleanrooms and associated controlled

environments Part 1: Classification of air cleanliness.

1 International Organization for Standardization, ISO Central

Secretariat, 1, rue de Varembé, Case postale 56, CH-1211 Geneva 20,

Switzerland. Telephone: 41.22.749.01.11; Fax: 41.22.733.34.30,

Website: www.iso.ch