Electrostatic Discharge (ESD) Protective …

1 Application ReportSZZA027A - April 20021 Electrostatic Discharge (ESD) ProtectiveSemiconductor Packing Materials and ConfigurationsCles Troxtell and James HuckabeeStandard Linear & LogicABSTRACTThe Texas Instruments Standard Linear & Logic (SLL) Business Group uses anindustry-recognized material system to ensure that semiconductor devices are adequatelyprotected from Electrostatic Discharge (ESD) damage during shipping and materials are selected and tested in accordance with internal specifications thatmeet or exceed current industry standards. The methods employed ensure correctcomponent materials are used at each factory location. End users of the standardcomponents often need to peruse many TI and industry publications to understand theESD- Protective configurations. This application report documents the tape-and-reel ESDconfigurations and provides a cogent explanation of the methods employed to test, evaluate,and deploy proper ESD- Protective packing-material.

2 Background3.. Standards for Protection of Devices from ESD During Shipping and Handling3.. Specific ESD Requirements for Packing Materials4.. Stick Magazine4.. Matrix Tray5.. Tape and Reel6.. Typical ESD- Protective Packing-Material Configurations6.. Stick Magazine6.. Tray7.. Tape and Reel8.. Static Voltage Test on Loaded Tape-and-Reel Material9.. Test Requirements for Material Properties Confirmation 10.. Conclusions14.. Acknowledgments14.. References14.. Glossary15.. Trademarks are the property of their respective Discharge (ESD) Protective Semiconductor Packing Materials and ConfigurationsList of Figures1 Shipping Magazine5.. 2 Matrix Tray With Devices in Place5.. 3 Typical Reel Loaded With Carrier Tape6.. 4 Bag/Magazine Packing Example7.. 5 Tray Packing-Material Example7.. 6 Tape-and-Reel Packaging Example8.. 7 Tape-and-Reel Configuration9.. 8 Six Locations Used to Expose the Units to a 20-kV Field10.

3 9 Charged-Plate Placement10.. 10 Typical Peeling Test11.. 11 Typical Unrolling Test11.. 12 Typical Cover-Tape Charge-Generation Test12.. List of Tables1 Measured Surface Resistivity of Carrier Tape13.. 2 Static Properties13.. SZZA027A3 Electrostatic Discharge (ESD) Protective Semiconductor Packing Materials and ConfigurationsIntroductionThe purpose of this application report is to describe in detail the methods used to test, evaluate,and deploy proper packing materials that protect against Electrostatic Discharge (ESD) damageto semiconductor devices. This application report provides customers with answers to the mostfrequently asked questions and allows them to review different ESD- Protective packingconfigurations and how those configurations apply to the devices they receive and sources addressed are those of the environment and ESD that might be created byinteractions between the packing material and the environment or devices the material invention of the transistor, and later, the integrated circuit, led to the development ofimproved methods for packing, shipping, and handling of electronic devices.

4 The semiconductordesign and manufacturing process often results in specific devices having varying degrees ofsusceptibility to damage from ESD. Manufacturers must design their assembly processes toensure that the devices are protected from ESD during the manufacturing process. Additionally,the materials used to pack the devices for delivery to customers must not only adequatelyprotect the devices mechanically, but also prevent damage from inadvertent exposures tohigh-intensity static for Protection of Devices from ESDD uring Shipping and HandlingThe electronics industry has published accepted standards to ensure reasonable conformanceamong multiple manufacturers of general requirements for packing containers are presented in EIA-383, Preparation forDelivery of Electrical and Electronic (June 24, 1988), Packaging Material Standards for ESD Sensitive Items, providesgeneral and specific requirements for ESD properties of packing material.

5 General requirementsfor maintaining antistatic and resistivity properties of packing materials, including conditions forverification of ESD properties of the packing materials, are technical requirements for packing materials for magazines, bags and pouches, flexiblecushioning materials, chipboard and corrugated cartons and boxes, loose filled, small moldedand irregular-shaped materials, rigid foams, carrier foam, and lead-insertion foam are (December 1999), Requirements for Handling Electrostatic - Discharge -Sensitive(ESDS) Devices, provides the minimum requirements for ESD-control methods and materialsused to protect electronic devices that are susceptible to damage, including degradation ofperformance, from Electrostatic , EIA-541 and JESD625-A detail the ESD requirements from the earliest steps in theassembly process to the final packing, shipping, and handling of the finished Instruments internal ESD specification (QSS 014-001) is based on the requirements ofJESD625 and references Discharge (ESD) Protective Semiconductor Packing Materials and ConfigurationsSpecific ESD Requirements for Packing MaterialsTwo ESD properties must be exhibited by packing materials.

6 Provide ESD protection Limit triboelectric charging to levels that do not result in device damageESD protection must be a barrier or enclosure that limits penetration of an Electrostatic field sothat its effects are attenuated sufficiently to prevent damage to the contained devices. Thesematerial properties are commonly called charging must be prevented by using materials that minimize the charge whenrubbed against, or separated from, themselves or similar materials. These material propertiesare commonly called requires that All ESDS devices shall be packed in an ESD Protective packagingwhen not at an ESD protected area or workstation, and further states that Packing and fillermaterials for ESDS devices shall be antistatic or static dissipative. The packing materials that provide ESD protection for the devices fall into two generalcategories that are defined in EIA-383.

7 The unit container and the first-level intermediatecontainer are discussed in this report. These containers incorporate all the necessary ESDprotection for the devices. In addition, filler or dunnage can be included, as needed, in either ofthe unit container has intimate contact with the device package body and/or leads. In mostcases, an automated pick-and-place process places the device is in its Instruments uses several different containers, which are described in the MagazineThe stick magazine (also called shipping tube) was developed in the early days of the ICindustry. The magazine is used in the manufacturing plant and for transport/storage from themanufacturer of the electronic devices to the customer. Magazines also are used to feed devicesto automatic placement machines for surface and through-hole board mounting. Multiple stickmagazines are placed in next-level intermediate containers (boxes or bags) in standard packingquantities.

8 Figure 1 shows an example of a stick are constructed of rigid, clear or translucent polyvinylchloride (PVC) material that isextruded as applicable standard outlines that meet current industry standards. The magazineprotects the device during shipping and handling. The magazine dimensions provide properdevice location and orientation for standard industry automated assembly extruded, PVC is an insulator and is subject to triboelectric charging. The extrudedmagazines receive a surface treatment to lower the surface resistivity of the PVC. EIA-541defines a static dissipative material as having a surface resistivity equal to or greater 105 per square, but less than 1012 per Electrostatic Discharge (ESD) Protective Semiconductor Packing Materials and Configurations Figure 1. Shipping MagazineMagazine manufacturers coat individual tubes with an antistatic solution, usually by dipping thetubes in a liquid solution then drying pins or end plugs retain devices in the magazine.

9 The pins and plugs are PVC and aretreated to ensure that surface resistivity is within the static-dissipative TrayMatrix trays are constructed of carbon powder or carbon-fiber materials that are selected basedon the maximum temperature rating of the specific tray. TI trays that are designed for use withdevices that require exposure to high temperatures (moisture-sensitive devices) havetemperature ratings of 150 C, or are molded into rectangular JEDEC-standard outlines containing matrices of uniformlyspaced pockets. The pocket cradles the device for protection during shipping and handling. Thespacing provides exact device locations for standard industry automated-assembly equipmentused for pick-and-place board-assembly processes. Figure 2 is an example of a typical 2. Matrix Tray With Devices in PlaceSZZA027A6 Electrostatic Discharge (ESD) Protective Semiconductor Packing Materials and ConfigurationsTape and ReelThe tape-and-reel configuration is used for transport/storage from the manufacturer of thedevices to the customer, and for use in the customer s manufacturing plant (see Figure 3).

10 Theconfiguration is designed for feeding devices to automatic-placement machines for surfacemounting on board assemblies. The configuration can be used for all SMT packages andprovides device lead isolation during shipping, handling, and processing. The completeconfiguration consists of a carrier tape with sequential individual cavities that each holds onedevice, and a cover tape sealed onto the carrier tape to retain the devices in the cavity. In mostcases, single reels of devices are inserted into intermediate boxes prior to 3. Typical Reel Loaded With Carrier TapeTypical ESD- Protective Packing-Material ConfigurationsStick MagazineIndividual devices are inserted into single magazines and secured with appropriate end pins orplugs. Then, multiple magazines are inserted into the intermediate container in this case, atwo-layer carbon-lined from ESD is provided by ensuring that packing materials in proximity to the devicesare not static generative and the entire intermediate container forms a Faraday shield to protectall the enclosed devices from external static voltages.