semi合集-English.pdf - 第216页
SEMI E28-92 © SEMI 1992, 2004 4 5.5.1.1 Example — Pressure coefficient of span may be expressed as: 0.1% of rea din g 240 kPa - 220 k Pa 0.005 % of re adin g/kPa w ith N 2 NOTE 9: If the relation between gas pres sure …
SEMI E28-92 © SEMI 1992, 2004 3
4.1.10 MFC calibration pressure, inlet and outlet —
the inlet and outlet pressure at which the MFC was
calibrated (see Figure 2).
4.1.11 normal operating pressure, inlet and outlet —
the pressure range within which the MFC meets its
stated performance specifications (see Figure 2).
4.1.12 normal operating differential pressure — the
range of differential pressure (see Section 4.1.5)
required by the MFC to meet its stated performance
specifications.
NOTE 6: The upper and lower limits are dependent upon the
absolute inlet or outlet pressure. These limits are
manufacturer-specific.
4.1.13 outlet pressure — the pressure at the outlet
fitting of the MFC (see Figure 3).
NOTE 7: To completely specify the pressure operating
environment for MFCs, at least two of the following three
pressures must be listed: inlet, outlet, and differential.
4.1.14 proof pressure — the maximum gas pressure
the MFC may be subjected to without permanent
damage. Some adjustment may be necessary to make it
meet its specified performance when returning to
normal operating pressure. (see Figure 2.)
4.1.15 reference ambient — the composition and
pressure range of the ambient medium surrounding the
MFC within which performance specifications apply
without requiring correction for changes in the ambient
medium.
4.1.16 reference operating pressure, inlet and outlet —
the range of gas pressures on the inlet of the MFC and
across the MFC within which performance
specifications apply without requiring correction for gas
pressure effects (see Figure 2).
4.1.17 standard pressure — SEMI E12 defines
standard pressure as 760 Torr (101.32 kPa) (see Figure
2).
5 Gas Pressure Effects
5.1 Specified Gas — Gas pressure effects may be gas
species sensitive. The gas must be specified when
stating gas pressure effects. Nitrogen is recommended
as the standard gas.
5.2 Pressure Measurement Point — In this section,
pressure is assumed to be measured at the fitting of the
MFC, inlet or outlet, that is adjacent to the flow
transducer.
5.3 Total Calibration Effect — The change in output,
including zero and span, due to a change in gas pressure
from one normal operating pressure to a second normal
operating pressure. All other conditions must be held
within the limits of reference operating conditions.
5.4 Zero Calibration Effect — the change in zero due
to a change in gas pressure from one normal operating
pressure to a second normal operating pressure. All
other conditions must be held within the limits of
reference operating conditions.
5.4.1 The effect of gas pressure change on zero may be
expressed as a coefficient calculated as the ratio of full-
scale percent change in output to the corresponding
change in gas pressure. The change in gas pressure
should be specified. This coefficient is defined as the
“pressure coefficient of zero.”
5.4.1.1 Example — Pressure coefficient of zero may be
expressed as:
0.2% of full scale
240 kPa - 220 kPa
0.01% of full scale/kPa with N
2
NOTE 8: If the relation between gas pressure and change in
output is linear, one coefficient will suffice.
5.4.2 If the gas pressure influence is non-linear, a
different method of expression may be used. Two
examples:
5.4.2.1 The percent of full-scale change in output will
not exceed a specified value for any value of gas
pressure within a specified gas pressure range.
5.4.2.1.1 Example — “± 0.15% of full-scale maximum
error over 200 kPa to 250 kPa with N
2
”
5.4.2.2 It may be desirable to state a series of
coefficients for successive increments of gas pressure
within a specified gas pressure range.
5.5 Span Calibration Effect — The change in span due
to a change in gas pressure from one normal operating
pressure to a second normal operating pressure. All
other conditions must be held within the limits of
reference operating conditions.
5.5.1 The effect of gas pressure change on span may be
expressed as a coefficient calculated as the ratio of
percent of reading change in output to the
corresponding change in gas pressure. The change in
gas pressure should be specified. This coefficient is
defined as the “pressure coefficient of span.”
SEMI E28-92 © SEMI 1992, 2004 4
5.5.1.1 Example — Pressure coefficient of span may
be expressed as:
0.1% of reading
240 kPa - 220 kPa
0.005% of reading/kPa with N
2
NOTE 9: If the relation between gas pressure and change in
output is linear, one coefficient will suffice.
5.5.2 If the gas pressure influence is non-linear, a
different method of expression may be used. Two
examples:
5.5.2.1 The percent of span change in output will not
exceed a specified value for any value of gas pressure
within a specified pressure range of a particular gas.
5.5.2.1.1 Example — “± 0.1% of reading maximum
error over 200 kPa to 250 kPa with Nitrogen”
5.5.2.2 It may be desirable to state a series of
coefficients for successive increments of gas pressure
within a specified pressure range.
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 or equipment mentioned
herein. These standards are subject to change without
notice.
By publication of this standard, Semiconductor
Equipment and Materials International (SEMI) takes no
position respecting the validity of any patent rights or
copyrights asserted in connection with any items
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.
Copyright by SEMI® (Semiconductor Equipment and Materials
International), 3081 Zanker Road, San Jose, CA 95134. Reproduction of
the contents in whole or in part is forbidden without express written
consent of SEMI.
SEMI E29-93 © SEMI 1993, 2004 1
SEMI E29-93 (Reapproved 1104)
STANDARD TERMINOLOGY FOR THE CALIBRATION OF MASS FLOW
CONTROLLERS AND MASS FLOW METERS
This standard was technically approved by the Global Gases Committee and is the direct responsibility of the
North American Gases Committee. Current edition approved by the North American Regional Standards
Committee on July 11, 2004. Initially available at www.semi.org September 2004; to be published
November 2004. Originally published in 1993; last published February 1999.
1 Purpose
1.1 This standard defines terms commonly used in the
calibration of mass flow controllers (MFC) and mass
flow meters (MFM). It is intended to provide for
worldwide terminology to be used by manufacturers
and users.
2 Scope
2.1 This standard defines terminology related to
MFC/MFM calibration. At present, there are often
several words used by the semiconductor industry to
describe the same concept or device. This standard is
intended to eliminate confusion and provide for a
common language which users and manufacturers can
employ to discuss MFC/MFM calibration.
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 standard attempts to provide basic definitions.
In some instances, it may be impossible to provide
definitions which thoroughly explain a concept. It is
suggested, in such instances, that the user consult other
sources or SEMI standards related to this topic.
4 Referenced Standards
4.1 SEMI Standards
SEMI E12 — Standard for Standard Pressure and
Standard Temperature for Flow Units Used in Mass
Flow Meters and Mass Flow Controllers
SEMI E18 — Guideline for Temperature Specifications
of the Mass Flow Controller
SEMI E28 — Guideline for Pressure Specifications of
the Mass Flow Controller
NOTICE: Unless otherwise indicated, all documents
cited shall be the latest published versions.
5 Terminology
5.1 Definitions
5.1.1 attitude — for mass flow controllers and mass
flow meters, the relationship between the base
mounting plane of the MFC, the gas flow direction and
the gravity vector. It may be stated as horizontal (base
down), vertical (inlet up), vertical (inlet down),
horizontal (upside down), or horizontal (either side
down).
5.1.2 calibration gas — for mass flow controllers and
mass flow meters, the gas which is flowed while the
device is being calibrated.
5.1.3 calibration temperature — for mass flow
controllers and mass flow meters, the ambient
temperature at which the device is calibrated. (SEMI
E18)
5.1.4 mass flow controller (MFC) — a self-contained
device, consisting of a mass flow transducer, control
valve, and control and signal-processing electronics,
commonly used in the semiconductor industry to
measure and regulate the mass flow of gas.
5.1.5 mass flow meter (MFM) — a self-contained
device, consisting of a mass flow transducer and signal-
processing electronics, commonly used in the
semiconductor industry to measure the mass flow of
gas.
5.1.6 molar flow — the number of moles per unit of
time flowing in a closed channel.
5.1.7 nameplate gas — for mass flow controllers and
mass flow meters, the gas, as labeled on the product,
intended to be controlled or measured.
5.1.8 primary flow standard — a device or system
which measures flow using a method based on some or
all of the primary measurements of length, time,
temperature, volume, pressure, or mass.
5.1.9 process gas — for mass flow controllers and
mass flow meters, the principal gas which the user
requires the device to control or measure.
5.1.10 standard pressure — the pressure in pascals
specified as a reference for measurement and