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ANSI/ESD S20.20- 2021 16 (This annex is no t part of ESD Association Standard ANSI/ESD S20.20- 202 1) ANNEX D (INFORMATIV E) – RELATED DOCU MENTS The follow ing doc uments are li sted for further reference. Some document…

ANSI/ESD S20.20-2021

Technical Rationale for Deviation: The ESD sensitivity of wafers in front-end manufacturing

operations is significantly lower than after the die are separated. A ceiling-based room ionization

system is used in the EPA's covered in this ESD Control Plan. The purpose of this system is

primarily for contamination control. It will be utilized for reducing the charge on the many process

essential insulators typically present in any wafer fabrication facility. A wide-coverage (versus point-

of-use) ionization system is critical in any wafer fabrication facility to reduce electric fields on the

many process essential insulators. In limited critical operations where a tighter offset is deemed

required by engineering or the ESD program manager, peak ionizer offset voltage maximum

specification is ± 35 Volts.

Examples of Unacceptable or Unnecessary Tailoring Statements and Rationale

Example 1

Tailoring Statement: Seating as an ESD control item is not required because all personnel must

wear a grounded wrist strap when seated inside an EPA.

ANSI/ESD S20.20 Requirement Affected: Section 8.2 (personnel grounding), second paragraph:

"When personnel are seated at ESD protective workstations, they shall be connected to the

selected grounding / equipotential bonding system via a wrist strap system."

Why is this Tailoring Statement Unnecessary? The standard does not require ESD protective

seating. ESD protective seating is one of many 'optional' ESD control items for EPAs provided in

Table 3 of the standard. The actual requirement is for seated personnel to be connected to a

grounded wrist strap, and this is independent of whether ESD protective seating is used.

Example 2

Tailoring Statement: Nonessential insulators are not allowed inside the organization's EPAs in

designated areas.

ANSI/ESD S20.20 Requirement Affected: Section 8.3.1 (insulators), first paragraph, second

sentence: "All nonessential insulators shall be separated from any ESDS item by at least 300 mm".

Why is this Tailoring Statement Unnecessary? By not allowing nonessential insulators inside

EPAs, the ANSI/ESD S20.20 requirement to ensure all nonessential insulators are separated from

ESDS items by 300 mm is met. As a result, no tailoring statement is required.

Example 3

Tailoring Statement: The lower point to ground limit for worksurfaces used within the EPAs is

greater than 1.0 x 10

ohms instead of 0 ohms as required.

ANSI/ESD S20.20 Requirement Affected: Table 3, product qualification and compliance

verification 'point to groundable point' and 'point to ground' minimum resistance limit of 0 ohms as

tested using ANSI/ESD STM4.1 and ESD TR53, respectively. Also, in Sections 7.3 (product

qualification plan) and 7.4 (compliance verification plan), the required test limits provided in Table 3

shall be met.

Why is this Tailoring Statement Unnecessary? The lower limit established is within the limits of

ANSI/ESD S20.20. Since it is within the limits, tailoring is not required. This lower limit will be the

requirement of this facility.

ANSI/ESD S20.20-2021

(This annex is not part of ESD Association Standard ANSI/ESD S20.20-2021)

ANNEX D (INFORMATIVE) – RELATED DOCUMENTS

The following documents are listed for further reference. Some documents may be canceled.

However, this listing provides a reference of documents reviewed during the preparation of this

standard.

Military / U.S. Government

MIL-STD-3010, Federal Test Method Standard

MIL-PRF-81705, Barrier Materials, Flexible, Electrostatic Discharge Protective, Heat-Sealable

MIL-PRF-38534, Performance Specification: Hybrid Microcircuits, General Specification

MIL-PRF-38535, Performance Specification: Integrated Circuits (Microcircuits) Manufacturing,

General Specification

MIL-STD-883-3 Method 3015, Test method standard for microcircuits

MIL-STD-750-1 Method 1020, Test methods for semiconductor devices

MIL-PRF-19500, Semiconductor Devices, General Specification

MIL-STD-1686, Electrostatic Discharge Control Program for Protection of Electrical and Electronic

Parts, Assemblies and Equipment (Excluding Electrically Initiated Explosive Devices) – This

standard has been canceled.

MIL-HDBK-263, Electrostatic Discharge Control Handbook for Protection of Electrical and

Electronic Parts, Assemblies, and Equipment (Excluding Electrically-Initiated Explosive Devices) –

This handbook has been canceled.

MIL-M-38510, General Specification for Military Microcircuits - This standard is inactive.

MIL-DTL-82646, Plastic Film, Conductive, Heat Sealable, Flexible

MIL-PRF-87893, Workstations, Electrostatic Discharge (ESD) Control

MIL-STD-129, Marking for Shipment and Storage

MIL-STD-1285, Marking of Electrical and Electronic Parts

KSC-MMA-1985-79, Standard Test Method for Evaluating Triboelectric Charge Generation and

Decay

MIL-HDBK-103, List of Standard Microcircuit Drawings

Supplemental Information Sheet for Electronic QML-19500

Industry Standards

ANSI/IEEE-STD-142, IEEE Green Book (IEEE Recommended Practice for Grounding of Industrial

and Commercial Power Systems)

ANSI/ESD SP5.0, ESD Association Standard Practice for Electrostatic Discharge Sensitivity

Testing – Reporting ESD Withstand Levels on Datasheets

ANSI/ESDA/JEDEC JS-001, ESDA/JEDEC Joint Standard for Electrostatic Discharge Sensitivity

Testing – Human Body Model (HBM) – Component Level

ANSI/ESDA/JEDEC JS-002, ESDA/JEDEC Joint Standard for Electrostatic Discharge Sensitivity

Testing – Charged Device Model (CDM) – Device Level

ESD SP5.2, ESD Association Standard Practice for Electrostatic Discharge Sensitivity Testing -

Machine Model (MM) – Component Level

ANSI/ESD SP10.1, ESD Association Standard Practice for the Protection of Electrostatic

Discharge Susceptible Items – Automated Handling Equipment (AHE)

ANSI/ESD STM15.1, ESD Association Standard Test Method for the Protection of Electrostatic

Discharge Susceptible Items – Methods for Resistance Measurement of Gloves and Finger Cots

ANSI/ESD S20.20-2021

ANSI/ESD SP17.1, ESD Standard Practice for the Protection of Electrostatic Discharge

Susceptible Items – Process Assessment Techniques

ESD TR20.20, ESD Association Technical Report – Handbook for the Development of an

Electrostatic Discharge Control Program for the Protection of Electronic Parts, Assemblies, and

Equipment

JESD625, Requirements for Handling Electrostatic-Discharge-Sensitive (ESDS) Devices

IPC/JEDEC J-STD-033, Handling, Packing, Shipping and Use of Moisture Reflow, and Process

Sensitive Devices

TR3.0-02-05, Selection and Acceptance of Air Ionizers

ESDSIL, Reliability Analysis Center (RAC) ESD Sensitive Items List

JESD471, Symbol and Label for Electrostatic Sensitive Devices

IEC 61340-5-1, Protection of Electronic Devices from Electrostatic Phenomena – General

Requirements

VZAP, Electrostatic Discharge Susceptibility Data

ISO 9001, Quality Management Systems – Requirements