5340.doc - Semi

Background Statement for SEMI Draft Document 5340 REVISION TO SEMI E10-0312, SPECIFICATION FOR DEFINITION AND MEASUREMENT OF
EQUIPMENT RELIABILITY, AVAILABILITY, AND MAINTAINABILITY (RAM) AND
UTILIZATION NOTICE: A copy of the Document with revision markups showing the intended
changes is also provided as an aid to the voter in addition to the expected
final version. Additions are indicated by underline and deletions are
indicated by strikethrough.
Notice: This background statement is not part of the balloted item. It is
provided solely to assist the recipient in reaching an informed decision
based on the rationale of the activity that preceded the creation of this
Document. Notice: Recipients of this Document are invited to submit, with their
comments, notification of any relevant patented technology or copyrighted
items of which they are aware and to provide supporting documentation. In
this context, "patented technology" is defined as technology for which a
patent has issued or has been applied for. In the latter case, only
publicly available information on the contents of the patent application is
to be provided. Background Statement The Equipment RAMP Metrics Task Force proposes to letter ballot this
revision to the Document SEMI E10-0312. It includes a few substantial
improvements and affects enough sections of the Document that a line-item
ballot is not possible, and the entire Draft Document is being balloted as
a whole. The breakout of total time into the six basic equipment states of
productive (PRD), standby (SBY), engineering (ENG), scheduled downtime
(SDT), unscheduled downtime (UDT), and nonscheduled (NST) has not been
changed. None of the definitions of any metrics have changed and there are
no new metrics, nor any metrics removed. The Document now makes clear
distinctions between the SEMI E10 states and the accumulated time in each
of those states (e.g., the productive state (PRD) versus productive time). A primary accomplishment in this letter ballot is the introduction of a
substantial set of example calculations as a new section, Related
Information 2. This example covers a scenario for a five-module multi-path
cluster tool (MPCT) with three processing equipment modules, a handler
equipment module, and a mainframe equipment module organized into two
intended process sets (IPSs). The scenario exercises key features of the
SEMI E10 state tracking and metrics. An event-by-event description explains
how equipment module events become equipment module states, how equipment
modules states become IPS states, and how the IPS states become states for
the MPCT. All fundamental quantities for the metrics and the metrics
themselves are calculated for all equipment systems, including the
individual equipment modules, the IPSs, and the MPCT. Generating the example calculation exposed a weakness in the SEMI E10-0312
logic for determining the productive state for an IPS. Where previously, an
IPS in operations time would be productive if any equipment module was in
the productive state. This led to unexpected results when support equipment
modules like handlers are productive, but processing equipment modules are
not. The IPS state logic has been revised to make the IPS productive only
when processing equipment modules are productive. This interpretation
refines the notion of "intended function" for an IPS to exclude support
modules. This new interpretation is also more consistent with SEMI E79's
treatment of MPCT metrics that only include
processing equipment modules. The task force believes that there are no
tradeoffs or sacrifices in making this logic change; only benefits. This letter ballot adds a brief new section, Related Information 3. This
section presents reporting conventions taken from the now Inactive SEMI E58
(ARAMS) Document, including standard color codes for the SEMI E10 states
and updated numerical codes and names of some SEMI E10 substates. This
section does not include any other content from SEMI E58, for example
regarding state model behavior or host communications. Inclusion of this
content allows interested users to access it from SEMI E10 separately
without procuring a copy of SEMI E58. Another new section, Related Information 4, presents guidance to the
industry on where to draw SEMI E10 productive time boundaries. This is
accomplished by referencing SEMI equipment automation Standards state
models and identifying states in those standards where SEMI E10 productive
time is active. Next, there are numerous editorial clarifications throughout all sections
of the Document. A great majority of these changes are for mutual
consistency of SEMI E10 with SEMI E79. Some of these changes are for
clarification. A few others are errata leftover from versions of SEMI E10
prior to E10-0312 that are inconsistent with the primary changes approved
in SEMI E10-0312; these items should have been changed with the 0312
ballot, but were overlooked at that time. Last, this letter ballot includes an update of the entire Document to
conform to the most recent Style Manual. This Document is being balloted simultaneously with SEMI E79. It is the
objective of the Equipment RAMP Metrics Task Force, that upon approval of
these two letter ballots, that the Documents will be mutually consistent
and sufficiently clear and complete requiring no major technical content
changes until the next mandatory five-year review cycle. This would allow
the Task Force to turn its attention toward technical education of the SEMI
community and away from revisions.
Review and Adjudication Information | |Task Force Review |Global Technical Committee |
| | |Adjudication |
|Group: |Equipment RAMP Metrics |NA Metrics TC Chapter |
| |TF | |
|Date: |Wednesday, April 2, |Wednesday, April 2, 2014 |
| |2014 | |
|Time & Time |09:00-12:00 PDT |15:00-18:00 PDT |
|zone: | | |
|Location: |SEMI Headquarters |SEMI Headquarters |
|City, |San Jose, |San Jose, California/USA |
|State/Country|California/USA | |
|: | | |
|Leader(s): |David Busing |David Bouldin (Fab |
| |(Consultant) |Consulting) |
| |Steven Meyer (Intel) |Mark Frankfurth (Cymer) |
|Standards |Michael Tran (SEMI NA) |Michael Tran (SEMI NA) |
|Staff: |408.943.7019 |408.943.7019 |
| |mtran@semi.org |mtran@semi.org | This meeting's details are subject to change, and additional review
sessions may be scheduled if necessary. Contact the task force leaders or
Standards staff for confirmation. Telephone and web information will be distributed to interested parties as
the meeting date approaches. If you will not be able to attend these
meetings in person but would like to participate by telephone/web, please
contact Standards staff. SEMI Draft Document 5340 REVISION TO SEMI E10-0312, SPECIFICATION FOR DEFINITION AND MEASUREMENT OF
EQUIPMENT RELIABILITY, AVAILABILITY, AND MAINTAINABILITY (RAM) AND
UTILIZATION NOTICE: This Document was completely rewritten in 20114. Purpose This Document establishes a common basis for communication between users
and suppliers of semiconductor manufacturing equipment by providing a
standardized methodology for measuring reliability, availability, and
maintainability (RAM) and utilization performance of equipment in a
manufacturing environment.
Scope The Document defines six mutually exclusive basic states into which all
conditions and periods of time for an equipment system must fall. One state
called the unscheduled downtime state (UDT) defines a 'failed' state for an
equipment system. The measurement of equipment system reliability in this
Document concentrates on the relationship ofbetween equipment system
failures toand equipment system usage.
All metrics defined herein are applicable to equipment systems that include
noncluster tools, single-path cluster tools (SPCTs), equipment modules
within a multi-path cluster tool (MPCT), intended process sets (IPSs) of
equipment modules, and MPCTs. This Document defines a treatment of RAM and
utilization measurement for MPCTs by first defining performance of IPSs as
a function of equipment module-level performance, then defining MPCT
performance as a function of IPS performance. For each metric presented,
any special handling required for IPSs and MPCTs is defined.
This Document defines basic metrics for:
Reliability - Including mean time between failures and mean cycles between
failures.
Availability - Including total uptime, operational uptime, equipment-
dependent uptime, and supplier-dependent uptime.
Maintainability - Including mean time to repair, mean time to (perform)
preventive maintenance, mean time offline, total failure rate, and
impairment rate.
Utilization - Including total utilization and operational utilization.
Supporting material included in this Document addresses concepts for
measurement of mean time between failure (MTBF) uncertainty and reliability
growth and degradation.
NOTICE: SEMI Standards and Safety Guidelines do not purport to address all
safety issues associated with their use. It is the responsibility of the
users of the Documents to establish appropriate safety and health
practices, and determine the applicability of regulatory or other
limitations prior to use.
Limitations Automated tracking of equipment states and performan