WG 3 - TC 47/WG 3

IEC 62435-3:2020 describes the aspects of data storage that are necessary for successful use of electronic components being stored after long periods while maintaining traceability or chain of custody. It defines what sort of data needs to be stored alongside the components or dies and the best way to do so in order to avoid losing data during the storage period. As defined in this document, long-term storage refers to a duration that can be more than twelve months for products scheduled for long duration storage. Philosophy, good working practice, and general means to facilitate the successful long-term-storage of electronic components are also addressed.
NOTE: In IEC 62435 (all parts), the term "components" is used interchangeably with dice, wafers, passives and packaged devices.

IEC 62435-6:2018 on long-term storage applies to packaged or finished devices in long-term storage that can be used as part of obsolescence mitigation strategy. Long-term storage refers to a duration that can be more than 12 months for product scheduled for storage. Philosophy, good working practice, and general means to facilitate the successful long-term storage of electronic components are also addressed.

IEC 62435-4:2018 specifies long-term storage methods and recommended conditions for long-term storage of electronic components including logistics, controls and security related to the storage facility. Long-term storage refers to a duration that may be more than 12 months for products scheduled for long duration storage. The philosophy of such storage, good working practices and general means to facilitate the successful long-term storage of electronic components are also addressed.

IEC 62435-2:2017 is related to deterioration mechanisms and is concerned with the way that components degrade over time depending on the storage conditions applied. This part also includes guidance on test methods that may be used to assess generic deterioration mechanisms. Typically, this part is used in conjunction with IEC 62435-1:2017 for any device long-term storage whose duration may be more than 12 months for product scheduled for long duration storage.

IEC 62435-1:2017 on long-term-storage covers the terms, definitions and principles of long-term-storage that can be used in as an obsolescence mitigation strategy. Long-term storage refers to a duration that can be more than 12 months for products scheduled for long duration storage. Philosophy, good working practice, and general means to facilitate the successful long-term-storage of electronic components are also addressed.
This standard cancels and replaces IEC/PAS 62435 published in 2005. This first edition constitutes a technical revision.

IEC 62435-5:2017 is applicable to long-term storage of die and wafer devices and establishes specific storage regimen and conditions for singulated bare die and partial or complete wafers of die including die with added structures such as redistribution layers and solder balls or bumps or other metallisation. This part also provides guidelines for special requirements and primary packaging that contain the die or wafers for handling purposes. Typically, this part is used in conjunction with IEC 62435-1:2017 for long-term storage of devices whose duration can be more than 12 months for products scheduled for long duration storage.

IEC 62258-2:2011 specifies the data formats that may be used for the exchange of data which is covered by other parts of the IEC 62258 series, as well as definitions of all parameters used according to the principles and methods of IEC 61360. It introduces a Device Data Exchange (DDX) format, with the prime goal of facilitating the transfer of adequate geometric data between die manufacturer and CAD/CAE user and formal information models that allow data exchange in other formats such as STEP physical file format, in accordance with ISO 10303-21, and XML. The data format has been kept intentionally flexible to permit usage beyond this initial scope. It has been developed to facilitate the production, supply and use of semiconductor die products, including but not limited to wafers, singulated bare die, die and wafers with attached connection structures, minimally or partially encapsulated die and wafers. This standard reflects the DDX data format at version 1.3.0. With respect to the first edition, several parameters have been updated for this edition.
This publication is to be read in conjunction with IEC 62258-1:2009.

IEC/TR 62258-3:2010 has been developed to facilitate the production, supply and use of semiconductor die products, including:
- wafers,
- singulated bare die,
- die and wafers with attached connection structures,
- and minimally or partially encapsulated die and wafers. This report contains suggested good practice for the handling, packing and storage of die products. Success in manufacture of electronic assemblies containing die products is enhanced by attention to handling, storage and environmental conditions. This report provides guidelines taken from industry experience and is especially useful to those integrating die products into assemblies for the first time. It is also intended as an aid to setting up and auditing facilities that handle or use bare die products, from wafer fabrication to final assembly. This edition includes the following significant technical changes with respect to the previous edition.
1. Special requirements have been added throughout the document for optical die, where applicable. For example see 4.3 paragraph 4 and 10.1.3 paragraph 3.
2. The following new subclauses have been added:
- 4.4.6 ESD Guidelines
- 5.1 Wafer thinning
3. Subclause 5.2 (Singulation or die separation) has been renamed from the previous Subclause 5.1 (Wafer sawing) and has been expanded to included other methods of singulation or sawing, including:
- 5.2.2 Wafer scribing
- 5.2.3 Laser cutting
- 5.2.4 Dice before grind (DBG)
4. Subclause 5.3.7 (previous edition Subclause 5.2.7) has been changed to include optical and microwave die.
5. In Subclause 6.3, the Subclause 6.3.2 (Specialised wafer tubs) has been added to include wafer taubs specially handle and ship wafers that have not been singulated.
6. Two new Subclauses have been to Clause 6:
- 6.9 Handling and packing of thinned die or wafers
- 6.10 Packing materials and their reuse
7. A new subclause has been added to Subclause 9.6:
- 9.6.3 Use of packing material having sacrificial properties
8. Annex A (Planning checklist) has been updated throughout.
9. In Annex B (Material specifications) a new Subclause has been added:
- B.5 Adhesive gel tray material specifications.

IEC 62258-1:2009 has been developed to facilitate the production, supply and use of semiconductor die products, including:
- wafers,
- singulated bare die,
- die and wafers with attached connection structures,
- minimally or partially encapsulated die and wafers.
This standard defines the minimum requirements for the data that are needed to describe such die products and is intended as an aid to the design of and procurement for assemblies incorporating die products. It covers the requirements for data, including:
- product identity,
- product data,
- die mechanical information,
- test, quality, assembly and reliability information,
- handling, shipping and storage information.
The main changes that have been introduced in this edition have been to ensure consistency across all parts of the standard. The ordering of the subclauses, particularly in Clause 6, has been changed to be more logical and the text of some of the requirements has been amended to add requirements on further information as covered by IEC/TR 62258-4, IEC/TR 62258-7 and IEC/TR 62258-8. New requirements include information on permutability of terminals and functional elements (6.6.4) and moisture sensitivity for partially encapsulated devices (8.8).

IEC/TR 62258-8:2008(E), which is a technical report, has been developed to facilitate the production, supply and use of semiconductor die products, including wafers; singulated bare die; die and wafers with attached connection structures; minimally or partially encapsulated die and wafers. This Technical Report contains an EXPRESS model schema that describes the elements needed for data exchange and that will allow the implementation of the requirements of the IEC 62258-1, IEC 62258-5 and IEC 62258-6 standards, as well as providing an exchange structure that is complementary to those defined in IEC 62258-2. It is also complementary to and compatible with the questionnaire in IEC 62258-4.

This technical report has been developed to facilitate the production, supply and use of semiconductor die products, including: wafers, singulated bare die, die and wafers attached connection structures and minimally or partially encapsulated die and wafers. This report contains an XML schema that describes the elements needed for data exchange and that will allow the implementation of the requirements of IEC 62258-1, IEC 62258-5 and IEC 62258-6, as well as providing an exchange structure that is complementary to those defined in IEC 62258-2. It is also complementary to and compatible with the questionnaire in IEC/TR 62258-4.

This PAS applies to the long-duration storage of electronic components. Although it has always existed to some extent, obsolescence of electronic components, and particularly integrated circuits, has become increasingly intense over the last few years. Indeed, with the existing technological boom, the commercial life of a component has become very short compared with the life of industrial equipment such as those encountered in the aeronautical field, the railway industry or the energy sector. The many solutions enabling obsolescence to be resolved are now identified. However, selecting one of these solutions must be preceded by a case-by-case technical and economic feasibility study, depending on whether storage is envisaged for field service or production, for example: - remedial storage as soon as components are no longer marketed - preventive storage anticipating declaration of obsolescence Taking into account the expected life of some installations, sometimes covering several decades, the qualification times, and the unavailability costs, which can also be very high, the solution to be adopted to resolve obsolescence must often be rapidly implemented. This is why the solution retained in most cases consists in systematically storing components which are in the process of becoming obsolescent. The technical risks of this solution are, a priori, fairly low. However, it requires the perfect mastery of the implemented process, and especially of the storage environment, although this mastery becomes critical when it comes to long-term storage. All handling, protection, storage and test operations must be performed according to the state of the art.