semi合集-English.pdf - 第6860页

SEMI S2-0703a E © SEMI 1991, 2004 89 R14-8.3.3 Fault Tolera nt Equipment Control System With High Availability And Redundant Network — In Figures R14-2 through R14-6, the FECS enters a safe-state cond ition if a failure …

SEMI S2-0703a

Figure R14-6

Fail-To-Safe Equipment Control System with Combined Network for Standard and Fail-To-Safe

Communication and Separated Controller

SEMI S2-0703a

R14-8.3.3 Fault Tolerant Equipment Control System With High Availability And Redundant Network — In Figures

R14-2 through R14-6, the FECS enters a safe-state condition if a failure should occur; however, the production

process would be interrupted. In order to increase the availability of the automation system and therefore avoid

process downtime resulting from control system faults as well as faults and errors of components such as the power

supply, the industrial controller, the network connection, and the I/O modules need to be made redundant. Possible

architectures (see Figure R14-7) for achieving high availability include 2 oo 2, 2 oo 3, 2 oo 4, etc. (see R14-Section

9). Using fail-to-safe and high availability systems, injury to people or environmental damage can be prevented and

the production process can be continued without interruption.

Figure R14-7

Fault-Tolerant Equipment Control System with High Availability FECS and Redundant Network

R14-9 Guide to Assessment and Test Methods

R14-9.1 Assessment and testing of an electronic system (especially programmable systems) for safety integrity

levels (SIL) according to IEC 61508/ANSI/ISA-84.01 or risk categories according to ISO 13849-1 (EN 954-1) is a

complex and time consuming task, requiring a considerable level of knowledge and expertise. The use of

components such as safety PLCs and safety networks, that are certified by third parties for use in systems, and

include specific SILs and risk categories, simplifies the process of assessing the whole system.

NOTE 9: Certified (or listed) components need to be certified for functional safety use in safety critical systems. The final

integrated system should be fully assessed; using tools such as IEC 61508/ANSI/ISA-84.01 or ISO 13849-1 (EN954-1).

Assessments can often simplified by using combinations of certified components or FECS.

R14-9.2 Commissioning and Site Approval — Commissioning and site approval as described in IEC 61508 may be

confusing and therefore the following criteria are necessary for understanding:

R14-9.2.1 Safety-related components should meet the safety requirements defined during the risk analysis.

NOTE 10: Use of Notified Bodies, ATLs or a Professional Engineer to perform system assessment, type approval/site

approval/commissioning of electronic components and for machinery with industrial controllers is defined by the jurisdiction of

use.

R14-9.2.2 During control system commissioning, all relevant documentation of the pre-inspection should be

available. A pre-inspection usually is the first phase of a control system commissioning.

SEMI S2-0703a

R14-9.2.3 During pre-inspection, control system

commissioning protocols should be prepared.

R14-9.2.4 If a safety analysis or safety case has been

prepared for the specific installation, all documents

regarding this activity should be made available.

R14-9.2.5 Whether a safety analysis or safety case has

been prepared or not, a directory of available

documents should be generated.

R14-9.2.5.1 This list should include the titles, dates

and number of pages of all documents.

R14-9.2.5.1.1 If possible, all documents should also be

available in electronic form.

R14-9.2.5.2 The documentation should include:

a. Safety Specification (if possible as formal

specification),

b. Top-level diagram of the application (1 or 2

pages),

c. Technical implementation (e.g. block, flow

and timing diagrams),

d. Explanation of separation between safety

critical and not safety critical parts of the

application,

e. Safety handbooks of the system components

(safety handbooks of the safety controllers,

sensors and actuators),

f. Description of interfaces,

g. Specification of all safety relevant program

parts,

h. I/O documentation,

i. Software program documentation,

j. Wiring documents,

k. Diagram and listing of the interaction

between input- and output-data (e.g. safety

matrix, cause-effect diagrams or comparable

documents),

l. Cross reference listing,

m. Source programs on storage medium, and

n. Description of the procedure to verify, that

the documentation, respectively the files on

the storage medium, are identical to the

programs in the application (upload verify,

CRC checksums, or comparable).

R14-10 Safety Performance

R14-10.1 For details on how to achieve the necessary

safety system requirements, see ISO 13849.

NOTE 11: An update of document IEC 62061 is currently

under preparation, and it should be consulted for further

details.

R14-11 Application Examples

R14-11.1 Safety is important in semiconductor

equipment (especially in the area of wafer fabrication)

where toxic media (e.g. gases or chemicals), high-speed

motion, or lasers may be present. The following are

examples of some wafer fabrication equipment which

could be adapted to a FECS:

a. CVD

b. Cleaning Equipment

c. CMP

d. Diffusion/Oxidation

e. Dry Etch Systems

f. Epitaxy

g. Ion Implantation

h. Lithography

i. Physical Vapor Deposition

j. Vacuum Deposition

k. Wet Etch Systems

R14-12 Related Documents

R14-12.1 DIN V VDE Standards

DIN V VDE 19250 — Control Technology; Functional

Safety Aspects to be Considered for Measurement and

Control Equipment

24 VDE-Verlag GmbH, Bismarkstrasse 33, 10625 Berlin, Germany,