Technical Library | 2010-05-24 23:47:35.0
Die echte Integration zwischen ATE Flying Prober und Boundary Scan Tester, vorgestellt von Seica, kombiniert das Beste von beiden Testtechniken und multipliziert die Vorteile für den Anwender.
Technical Library | 2020-11-29 22:02:49.0
It has been over 25 years since the earliest edition of "Everything You Ever Wanted to Know About Laminates...but Were Afraid to Ask" was pounded out on an old TRaSh-80 Computer. It has undergone periodic review and editing, including adaption for use on our website. (When I entered the industry Al Gore had not yet invented the internet.) Before I "retired" in 2004, we did another minor revision, but it was largely cosmetic, removing most references to the old military specification and introducing IPC-4101, the "new" specification for laminate and prepreg materials.
Technical Library | 2014-07-24 16:26:34.0
Wire bonding a die to a package has traditionally been performed using either aluminum or gold wire. Gold wire provides the ability to use a ball and stitch process. This technique provides more control over loop height and bond placement. The drawback has been the increasing cost of the gold wire. Lower cost Al wire has been used for wedge-wedge bonds but these are not as versatile for complex package assembly. The use of copper wire for ball-stitch bonding has been proposed and recently implemented in high volume to solve the cost issues with gold. As one would expect, bonding with copper is not as forgiving as with gold mainly due to oxide growth and hardness differences. This paper will examine the common failure mechanisms that one might experience when implementing this new technology.
Technical Library | 2015-08-13 15:52:40.0
Pad cratering has become more prevalent with the switch to lead free solders and lead free compatible laminates. This mainly is due to the use of higher reflow temperature, stiffer Pb-free solder alloys, and the more brittle Pb-free compatible laminates. However, pad cratering is difficult to detect by monitoring electric resistance since pad cratering initiates before an electrical failure occurs. Several methods have been developed to evaluate laminate materials' resistance to pad cratering. Pad-solder level tests include ball shear, ball pull and pin pull. The detailed methods for ball shear, ball pull, and pin pull testing are documented in an industry standard IPC-9708. Bansal, et al. proposed to use acoustic emission (AE) sensors to detect pad cratering during four-point bend test. Currently there is an industry-working group working on test guidelines for acoustic emission measurement during mechanical testing.
Technical Library | 2009-03-27 22:22:40.0
The Sn-Ag-Cu (SAC) alloys have been considered promising replacements for the lead-containing solders for the microelectronics applications. However, due to the rigidity of the SAC alloys, compared with the Pb-containing alloys, more failures have been found in the drop and high impact applications for the portable electronic devices, such as the personal data assistant (PDA), cellular phone, notebook computer..etc
Technical Library | 2020-07-29 19:58:48.0
The majority of flexible circuits are made by patterning copper metal that is laminated to a flexible substrate, which is usually polyimide film of varying thickness. An increasingly popular method to meet the need for lower cost circuitry is the use of aluminum on Polyester (Al-PET) substrates. This material is gaining popularity and has found wide use in RFID tags, low cost LED lighting and other single-layer circuits. However, both aluminum and PET have their own constraints and require special processing to make finished circuits. Aluminum is not easy to solder components to at low temperatures and PET cannot withstand high temperatures. Soldering to these materials requires either an additional surface treatment or the use of conductive epoxy to attach components. Surface treatment of aluminum includes the likes of Electroless Nickel Immersion Gold plating (ENIG), which is extensive wet-chemistry and cost-prohibitive for mass adoption. Conductive adhesives, including Anisotropic Conductive Paste (ACP), are another alternate to soldering components. These result in component substrate interfaces that are inferior to conventional solders in terms of performance and reliability. An advanced surface treatment technology will be presented that addresses all these constraints. Once applied on Aluminum surfaces using conventional printing techniques such as screen, stencil, etc., it is cured thermally in a convection oven at low temperatures. This surface treatment is non-conductive. To attach a component, a solder bump on the component or solder printed on the treated pad is needed before placing the component. The Aluminum circuit will pass through a reflow oven, as is commonly done in PCB manufacturing. This allows for the formation of a true metal to metal bond between the solder and the aluminum on the pads. This process paves the way for large scale, low cost manufacturing of Al-PET circuits. We will also discuss details of the process used to make functional aluminum circuits, study the resultant solder-aluminum bond, shear results and SEM/ EDS analysis.
Technical Library | 2023-01-10 20:15:42.0
Over the past years there has been consistent growth in the use of electroless nickel / immersion gold (ENIG) as a final finish. The finish is now frequently being used for PBGA, CSP, QFP and COB and more recently gathered considerable interest as a low cost under-bump metallization for flip chip bumping application. One of the largest users for this finish has been the telecommunication industry, were millions of square meters of PCBs with ENIG have been successfully used. The nickel layer offers advantages such as multiple soldering cycles and hand reworks without copper dissolution being a factor. The nickel also acts as a reinforcement to improve through-hole and blind micro via thermal integrity. In addition the nickel layer offers advantages such as co-planarity, Al-wire bondability and the use as contact surface for keypads or contact switching. Especially those pads, which are not covered by solder need a protective coating in corrosive environment – such as high humidity or pollutant gas.
Technical Library | 1999-05-07 10:11:55.0
The Intel StrataFlashTM memory technology represents a cost breakthrough for flash memory devices by enabling the storage of two bits of data in a single flash memory transistor. This paper will discuss the evolution of the two bit/cell technology from conception to production.
Technical Library | 1999-05-07 10:13:38.0
This paper will review the device physics governing the operation of the industry standard ETOX™ flash memory cell and show how it is ideally suited for multiple bit per cell storage, through its storage of electrons on an electrically isolated floating gate and through its direct access to the memory cell.
Technical Library | 2021-06-07 19:03:05.0
The waste from end-of-life electrical and electronic equipment has become the fastest growing waste problem in the world. The difficult-to-treat waste-printed circuit boards (WPCBs), which are nearly 3−6 wt % of the total electronic waste, generate great environmental concern nowadays. For WPCB treatment and recycling, the mechanical−physical method has turned out to be more technologically and economically feasible. In this work, the mechanical−physical treatment and recycling technologies for WPCBs were investigated, and future research was directed as well. Removing electric and electronic components(EECs) from WPCBs is critical for their crushing and metal recovery; however, environmentally friendly and high-efficiency removal techniques need be developed. Concentrated metals rich in Cu, Al, Au, Pb, and Sn recovered from WPCBs need be further refined to add to their economic values. The low value added nonmetallic fraction of waste-printed circuit boards (NMF-WPCBs) accounts for approximately 60 wt % of the WPCBs. From the perspective of environmental management, a zero-waste approach to recycling them should be developed to gain values. Preparing polymer composites and geopolymers offers many advantages and has potential applications in various fields, especially as construction and building materials. However, the mechanical and thermal properties of NMF-WPCBs composites should be further improved for preparing polymer composites. Surface modification or filler blending could be applied to improve the interfacial comparability between NMF-WPCBs and the polymer matrix. The NMFWPCBs shows potential in preparing cement mortar and geological polymers, but the environmental safety resulting from metals needs to be taken into account. This study will provide a significant reference for the industrial recycling of NMF-WPCBs
