SEMI International Standards
Standards New Activity Report Form (SNARF)
Date Prepared: 04/02/2010Revised (if Applicable): 09/21/2011

Document Number: 4922
SNARF for: New Standard: Guide for Equipment Fan Filter Unit (EFFU) Performance

Originating Global Technical Committee: Facilities
Originating TC Chapter: Korea
Task Force (TF) in which work is to be carried out: Equipment Cleanness Task Force
Note: If a new task force is needed, also submit a task force organization form (TFOF)

1. Rationale:
a. Describe the need or problem addressed by this activity.
(Indicate the customer, what benefits they will receive, and if possible, quantify the impact on the return on investment [ROI] if the Document is implemented.)
When the level of cleanliness in semiconductor equipment is not satisfied, it causes interfaces between thin films on raw wafer to be contaminated and leads to not only declination of electronics but also shortening the life time of chips. Therefore, it is extremely essential to keep production line of semiconductor constantly.

Manufacturers of semiconductor equipment should present performance specifications of EFFUs (Equipment Fan Filter Units) to EFFUs suppliers in order to achieve highest yield rate during mass semiconductor production However, semiconductor equipment makers unfortunately do not present EFFUs performance specifications to EFFUs suppliers. Therefore, it induces a variety of types in EFFUs to spread out depending on various types of semiconductor equipment. It causes diversification of EFFUs in performance specification as well as sizes.

In accordance with many different kinds of EFFUs in performance, the guide in performance levels for EFFUs which leads to most efficient productivity in semiconductor manufacture line is desperately needed to reduce energy waste.

b. Estimate effect on industry.
2: Major effect on an industry sector - identify the relevant sector
Sector or Company Information:

c. Estimate technical difficulty of the activity.
II: Some Difficulty - Disagreements on known requirements exist but developing consensus is possible

2. Scope:
a: Describe the technical areas to be covered or addressed by this Document development activity. For Subordinate Standards, list common concepts or criteria that the Subordinate Standard inherits from the Primary Standard, as well as differences from the Primary Standard:
This standard provides common guide for EFFUs which work out during operation and is mainly focusing on power consumption and airflow circulation. It recommends the EFFUs standard performance to all EFFUs manufacturers and vendors in order that EFFUs can be upgraded to most compatible and competitive parts as well as lowest energy consumption. It also can be referenced by and integrated into a relevant industry recommended for field practice or suggestions of standard.

The recommendation for the EFFUs standard performance includes following items:

-Average velocity specified with tolerance 5%
-CMM (cubic meter per minute) specified with tolerance 5%
-airflow uniformity with standard deviation divided by average airflow velocity equal to or less than 0.25
-equal to or less than 6.5 W/CMM (watt/CMM)
-equal to or less than 65 dBA of sound noise level
-degree of vibration equal to or less than 1mm

The test procedure instruction for the characterization of EFFUs includes following items:

1. Test method for measuring average velocity with unit of meter per second.
- The number of measuring point of average velocity are determined by the computational result of equation as the number of measuring point = filter area(m X m) of air going through divided by 4 times 100.
- Each location of measuring point is determined by dividing filter area of EEFU by the number of measuring point and allocating a measuring point to center of each sub-area.
- Average velocity is measured utilizing 3-dimensional wind velocimeter at each point allocated by 5cm distanced vertically away with laminar flow remained from the filter face.

2. Test method of CMM which means cubic meter per minute as airflow rate coupled with total pressure of EFFU.
- Pressure differential is measured between front and rear of the nozzle which airflow goes through inside air chamber.
-CMM is calculated using Bernoulli equation and flow continuity equation.

3. Test method of airflow uniformity measured at several locations vertically far away with laminar flow remained from air-filter.
- maintain in order that standard deviation of wind velocity at several locations may be equal or less than 0.05 based on the test method described in section 1. above.

4. W/CMM where W means wattage as power consumption while CMM is described as above.
- divid power consumption of EFFU by airflow rate obtained satisfactorily from test method described in section 2 and 3 above.

5. Test method of sound noise level
- repeatedly measure sound noise level by three times at distance away 1m vertically from filter under the condition of anechoic sound noise level equal to or less than 30dB.
- respective value of sound noise level is repeatedly measured three times in the range of 4 Hz to 3.2KHz for 20 seconds.
- average 3 values of sound noise level

6. Test method of vibration
- structure like two cantilevers supporting only two wide edges at bottom face of EFFU is formed while one longitudinal edge at bottom face of EFFU is free of fixation.
- an vibration sensor is attached at the center on one side face among 4 side faces of filter in order to measure displacement of EFFU in operation.
- repeatedly measure vibration by three times with pressure loaded.
- respective value of vibration is repeatedly measured three times utilizing 3-axial sensing of vibration in the range of 0 Hz to 400 Hz for 20 seconds.
- average 3 values of vibration

The objective of this standard is to provide instruction for performance testing and reporting based upon consistent procedures. This can be referenced by and integrated into a relevant industry recommended for field practice or suggestions of standard.

The options is CMM is calculated by multiplying filter area of airflow going through by average velocity.
The other option is CMM is calculated using Bernoulli equation and flow continuity equation after pressure differential is measured between front and rear of the nozzle which airflow goes through inside air chamber.

However, it is recommend to measure CMM derived from experimental measurement of pressure differential inside air chamber because value of CMM computed from only multiplying average velocity by filter area is less accurate than that of CMM calculated using conservation of mass and energy containing pressure differential measured.

b: Expected result of activity
New Standard

For a new Subordinate Standard, identify the Primary Standard here:

For Standards, identify the Standard Subtype below:

Miscellaneous (describe below):

3. Projected Timetable for Completion:

a: General Milestones
a. Activity Start: 03/01/2010b. 1st Draft by: 10/17/2011
c. (Optional) Informational Ballot by: d. Letter Ballot by: 10/17/2011
e. TC Chapter Approval By:06/30/2012

4. Liaisons with other Global Technical Committees/TC Chapters/Subcommittees/TFs:
List global technical committees, TC Chapters, subcommittees, or task forces in your or other Regions/Locales that should be kept informed regarding the progress of this activity. (Refer to SEMI Standards organization charts and global technical committee charters as needed.)
Global Facilities

b. Intercommittee Ballots:

Identify the recipient global technical committee(s):

5. Safety Considerations:
The resulting document is expected:
NOT to be a Safety Guideline

NOTE FOR "to be a Safety Guideline": When all safety-related information is removed from the Document, the Document is NOT technically sound and complete - Refer to Section 15.1 of the Regulations for special procedures to be followed.

NOTE FOR "NOT to be a Safety Guideline": When all safety-related information is removed from the Document, the Document is still technically sound and complete.

6. Intellectual Property Considerations:
a. For a new Standard or Safety Guideline and for any part to be modified or added in a Revision of published Standards and Safety Guidelines:
the use of patented technology or a copyrighted item(s) is NOT required

If "patented technology is intended to be included in the proposed Standard(s) or Safety Guideline(s) " is selected above, then also check one:

b. For Revision, Reapproval, Reinstatement, or Withdrawal of existing Standard(s) and Safety Guideline(s):

c. The body of the Document and any Appendices, Complementary Files, Related Information sections, or Various Materials that may or may not be a part of the Document by reference:
will NOT include copyrighted material

NOTE FOR "the use of patented technology or a copyrighted item(s) is NOT required": If in the course of developing the document, it is determined that patented technology or copyrighted item(s) must be used to comply with the standard or safety guideline, the provisions of Section 16 of the Regulations must be followed.)

NOTE FOR "will include reproduced copyrighted material": A copyright release letter must be obtained from the copyright owner.

7. Comments, Special Circumstances:
1. The SNARF was approved by NA Facilities on July 22, 2009 and it is transferred to Korea Facilities and approved on October 21, 2010
2. The transferred SNARF is also revised its scope and Document type from "Specification" to "Guide" on September 21, 2011.

8. TC Member Review:

Member Review Start Date; None.
Member Review End Date: None.

NOTE FOR ‘TC Member Review’ is required by the Regulations for a period of at least two weeks
before approval of a new, or a major revision of an existing, Standard or Safety Guideline. (See Regulations 8.2.1)
9.. SNARF Approval Dates:
TC Chapter or GCS03/30/2010
Recorded in TC Minutes09/21/2011
Attach Pictures and Files here: