SEMI International Standards
Standards New Activity Report Form (SNARF)
Date Prepared: 11/16/2023Revised (if Applicable):

Document Number: 7162
SNARF for: New Standard: Test Method for epi-resistivity determination in Si wafers by Surface Charge Profiling

Originating Global Technical Committee: Silicon Wafer
Originating TC Chapter: Europe
Task Force (TF) in which work is to be carried out: International Test Methods Task Force
Note: If a new task force is needed, also submit a task force organization form (TFOF)

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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.)
The standard technique for determination of the carrier density or resistivity in epitaxial Si-wafers is the CV (capacitance-voltage) measurement with a Mercury probe described in SEMI MF1392. However due to the environmentally critical use of Mercury a Hg-free method is needed.
The non-contacting, SPV-based Surface Charge Profiling (SCP) does not only close this gap, but also offers the possibility to do fast mappings of the wafer surface and thus provide information about the homogeneity of the resistivity distribution in the surface-near region.


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

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

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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 test method covers the measurement of the average resistivity or carrier density within the surface-near space charge region (SCR) in epitaxial wafers in the range from 0.03 to 50 Ohmcm (n-type) or 0.03 Ohmcm to 100 Ohmcm (p-type).

The method requires information from an AC-SPV signal generated in the surface-near SCR. A surface treatment is needed to ensure homogeneous inversion conditions throughout the whole wafer during the measurement. This treatment is different for p- and n-type samples. The SPV measurement is low invasive and non-contacting.

This test method may be applied to epitaxial layers on the same or opposite conductivity type substrate with or without an insulating back-seal layer, depending on the insulation conditions.

This test method provides average carrier density or resistivity within the SCR calculated from the depth (Wd) of the SCR. In addition, this test-method delivers information about the surface-controlled carrier recombination lifetime and the conductivity type.

Due to the short measurement time of a single location on the wafer, a mapping of the wafer’s surface is possible, thus providing information about the homogeneity of the above-mentioned parameters throughout the wafer’s surface.

A depth profiling like with a CV-type measurement is not possible.

A method for calibration and adjustment to ensure long-term stable results is included in this standard.

A proposal is made, which parameters should be monitored to ensure a stable measurement process, including preparation and measurement.

b: Expected result of activity
New Standard or Safety Guideline (including replacement of an existing Standard or Safety Guideline)

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




For Standards, identify the Standard Subtype below:
Test Method

Miscellaneous (describe below):

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3. Projected Timetable for Completion:

a: General Milestones
a. Activity Start: 11/01/2023b. 1st Draft by: 04/01/2024
c. (Optional) Informational Ballot by: d. Letter Ballot by: 07/01/2024
e. TC Chapter Approval By:11/01/2024

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4. Liaisons with other Global Technical Committees/TC Chapters/Subcommittees/TFs:
a. List SEMI 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 and scopes as needed.)


b. List any planned Type I Liaisons with external nonprofit organizations (e.g., SDO) that should receive Draft Documents from Standards staff for feedback during this activity and be notified when the Letter Ballot is issued (refer to Procedure Manual § 7):


c. Intercommittee Ballots:
will not be issued

Identify the recipient global technical committee(s):

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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.

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6. Intellectual Property Considerations:
Note: Both a: and b: below should be checked for Revision of existing Standard(s) and Safety Guideline(s).

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 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:
the incorporation of Copyrighted Item will NOT be required



NOTE FOR ‘the use of patented technology or the incorporation of Copyrighted Item(s) is NOT required’: If in the course of developing the Document, it is determined that the use of patented technology or Copyrighted Item(s) is necessary for the Document, the provisions of Regulations § 16 must be followed.

NOTE FOR ’will incorporate Copyrighted Item’: A copyright release letter must be obtained from the copyright owner prior to publication.

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7. Comments, Special Circumstances:
None.

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8. TC Member Review:
took place between (put dates below ) before approval at the TC Chapter Meeting, or

Member Review Start Date; 11/1/2023
Member Review End Date: 11/15/2023

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. (Refer to Regulations ¶ 8.2.1)
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9. SNARF Approval Dates:
TC Chapter or GCS11/16/2023
Recorded in TC Minutes11/16/2023

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10. SNARF Extension Dates:
TC Chapter Extension Granted on
Extension Expires on