GB/T 42706.2-2023Electronic components - Long-term storage of electronic semiconductor devices - Part 2: Deterioration mechanisms (English PDF)

Foreword

This document was issued on 23 May 2023 by the State Administration for Market Regulation; Standardization Administration of the PRC and takes effect on 1 September 2023.

It is a GB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

It is classified under ICS 31.020, Chinese classification L40.

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1. Structure and Drafting Rules for Standardization Documents"

drafting.

This document is part 2 of GB/T 42706 "Long-term Storage of Electronic Components and Semiconductor Devices". GB/T 42706 has been published

the following sections.

--- Part 1. General;

--- Part 2. Degradation mechanism;

--- Part 5. Chips and wafers.

This document is equivalent to IEC 62435-2.2017 "Long-term storage of electronic components and semiconductor devices - Part 2. Degradation mechanisms".

The following minimal editorial changes have been made to this document.

a) The informative reference to JEDEC JEP122 in 4.8 is deleted;

b) In Table A.1, in order to avoid confusion between the letter "T" in the last column and the same letter in the fourth column, change the letter "T" in the last column to

became the letter "C";

c) Adjusted references.

Please note that some contents of this document may refer to patents. The issuing agency of this document assumes no responsibility for identifying patents.

This document is proposed by the Ministry of Industry and Information Technology of the People's Republic of China.

This document is under the jurisdiction of the National Semiconductor Device Standardization Technical Committee (SAC/TC78).

This document is drafted by. The Thirteenth Research Institute of China Electronics Technology Group Corporation, Hebei Beixin Semiconductor Technology Co., Ltd., Chizhou Huayu

Electronic Technology Co., Ltd., Hebei Zhongdian Kehang Testing Technology Service Co., Ltd., Shenzhen Institute of Standard Technology, Beijing Saidi Junxin Electronics

Product Testing Laboratory Co., Ltd., Mianyang Micro Micro Testing Technology Co., Ltd., Wuhan Gewuxin Technology Co., Ltd., Huizhou Techuang Electronics

Technology Co., Ltd., Foshan Yifeng Electric Appliance Industry Co., Ltd.

The main drafters of this document. Liu Wei, Shi Dongsheng, Jin Lihua, Peng Yong, Yan Meng, Zhang Xin, Peng Hao, Cui Bo, Wei Bing, Zhao Peng, Mai Rirong, Xu Xin,

Mi Cunyan, He Li, Chen Jinxing, Wu Weibin.

Introduction

This document describes an implementation method for long-term storage. Long-term storage refers to electronic components that are expected to be stored for more than 12 months

storage.

In recent years, the elimination of electronic components, especially integrated circuits, has become more and more serious. With the development of science and technology, and used in aviation, railway or energy

Compared with industrial equipment in the source field, the life cycle of components is very short. Therefore, systematic storage of components is the solution to the elimination problem.

main method.

Long-term storage requires good implementation of storage procedures, especially the storage environment. It is recommended that all transport, maintenance

care, storage and testing operations.

This document proposes a method of delaying obsolescence to the greatest extent possible, but does not guarantee that components will be in perfect working condition after storage.

operating status.

Because some systems are very old, in some cases 40 years or more, how to perform repairs and obtain spare parts becomes a

The problems that users and maintenance organizations need to solve. For example, some components required to service these systems cannot be used during the life of the system

Spare parts obtained from the original supplier or used for assembly are produced at the beginning of production but require long-term storage. of this document

The purpose is to provide guidance for long-term storage of components.

GB/T 42706 "Long-term storage of electronic components and semiconductor devices" aims to ensure that after long-term storage of components, there is sufficient

reliability. Encourage users to ask suppliers to provide technical parameters of related products to demonstrate the storage process that meets user needs. These labels

The standard aims to provide relevant guidance for electronic components that require long-term storage.

GB/T 42706 "Long-term storage of electronic components and semiconductor devices" is divided into 9 parts. Part 1~Part 4 applies to

All long-term storage, and contains general requirements and guidance. Parts 5 to 9 apply to the storage of several specific product types. exist

While meeting the general requirements of Parts 1 to 4, the requirements for specific product types must also be met.

Beginning with Part 5, it deals with electronic components that require different storage conditions.

GB/T 42706 "Long-term Storage of Electronic Components and Semiconductor Devices" corresponds to the IEC 62435 series standards and is proposed to be divided into the following

part.

--- Part 1. General. The purpose is to specify the relevant terms, definitions and principles of long-term storage, and to provide effective long-term storage of components.

Storage concepts, good working practices and general methods.

--- Part 2. Degradation mechanism. The purpose is to specify the degradation mechanisms and

Mode of degradation, and guidance on test methods for assessing general degradation mechanisms.

--- Part 3. Data. The purpose is to specify the requirements for all aspects of data storage during the long-term storage of electronic components, and to maintain traceability.

traceability or data link integrity.

--- Part 4. Storage. The purpose is to specify the long-term storage method of electronic components, as well as related recommended conditions, including transportation, control

control and storage facilities.

--- Part 5. Chips and wafers. The purpose is to specify single chips, parts of wafers or entire wafers, as well as metallized structures (introduced

storage conditions and rules for chips, as well as general-purpose and special-purpose packaging products containing chips or wafers

Provide operational guidance.

--- Part 6. Packaged or coated components. The purpose is to specify the long-term storage methods and recommended conditions for packaged or coated components, including

including transport, containment, and storage facility security.

--- Part 7. MEMS. The purpose is to specify the matters needing attention and basic requirements for long-term storage of MEMS.

--- Part 8. Passive electronic devices. The purpose is to specify matters needing attention and basic requirements for long-term storage of passive electronic device products.

This requirement.

--- Part 9. Special circumstances. The purpose is to specify storage methods for special devices, including all types of silicon devices and semiconductors

device.

Long-term storage of electronic components and semiconductor devices

Part 2. Degradation Mechanisms

1 Scope

GB/T 42706.2-2023 addresses electronic semiconductor devices that are expected to sit in a store for more than twelve months before they are fitted, and the ways they deteriorate while nothing at all is being done to them. The degradation types are set out one at a time: the solderability of lead plating and its oxidation, the popcorn effect that appears when a package which has absorbed moisture meets reflow heat, the condition of the layers inside the package, corrosion and discoloration, electrostatic influence, damage from high-energy ionizing radiation, the risk that storage temperature itself poses to the device, and the behaviour of precious metal coatings. A further group of clauses gives the purpose of degradation testing, the criteria for selecting which tests to run, and the measurement and test methods themselves. Obsolescence is the reason any of this matters: aviation, railway and energy equipment stays in service for decades while the parts it uses go out of production, so operators buy a lifetime supply early and warehouse it. A device that will no longer wet with solder, or that cracks the first time it is heated, is discovered at assembly, years after the supplier has gone. Used together with IEC 62435-1, it serves the procurement and storage side of long-life electronics.

This document describes the degradation mechanisms and modes of electronic components over time under realistic storage conditions and

Mechanism test methods. Typically this document is used in conjunction with IEC 62435-1 for long-term storage where the expected storage time exceeds 12 months

device. The degradation mechanism of specific types of electronic components is specified in IEC 62435-5~IEC 62435-9.

2 Normative references

The contents of the following documents constitute the essential provisions of this document through normative references in the text. Among them, dated references

For documents, only the version corresponding to the date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to

this document.

IEC 60749-20-1 Mechanical and climatic test methods for semiconductor devices Part 20-1. Sensitivity to the combined effects of moisture and soldering heat

Note. GB/T 4937.201-2018 Mechanical and climatic test methods for semiconductor devices Part 20-1. Surfaces sensitive to the combined effects of moisture and soldering heat

Handling, packaging, marking and transportation of installation devices (IEC 60749-20-1.2009, IDT)

3 Terms, Definitions and Abbreviations

3.1 Terms and Definitions

The following terms and definitions apply to this document.

3.1.1

storage environment storage environment

A storage area that is specially controlled for temperature, humidity, atmospheric environment and other conditions according to the requirements of the product.

3.1.2

Long-term storage long-termstorage; LTS

In order to prolong the life cycle of products and meet the needs of later use, planned component storage is carried out.

3.1.3

moisture barrier bag; MBB

Storage bags with a flexible laminated vapor barrier film to limit the transmission of water vapor.

Note. See IEC 60749-20-1 for packaging of moisture sensitive products.

3.2 Abbreviations

The following abbreviations apply to this document.

BGA ball grid array (BalGridArray)

ES Electro-Static