Uyemura Introduces TWX-40 Mixed Reaction Autocatalytic Gold
February 21, 2018 | UyemuraEstimated reading time: 2 minutes
Uyemura has introduced TWX-40, an important technology development that allows gold deposits up to 8μin in ENIG and ENEPIG processing, in a single step.
The standard deposit for ENEPIG has been 1−2 µin of gold, a thickness now considered insufficient for certain OEM applications. Designers are now encountering applications demanding a minimum 3−5 µins gold in order to widen their operating window, add process flexibility, and assure the reliability of their wire bonding or pressure pin applications.
With standard immersion gold processes, heavier deposits on nickel or palladium in particular are problematic. To produce thicker deposits, shops are often forced to increase dwell time in the immersion gold, but with even minor porosity in the palladium layer, gold attacks the underlying nickel, leading to corrosion byproducts and poor reliability. The inevitable outcome of this nickel corrosion is two-fold: either wire bonds lift, or press pin connections become unreliable at the palladium-nickel interface.
One answer to this challenge has been to deposit autocatalytic gold over immersion gold—an additional step, requiring costly bath make-up for what is inevitably a limited bath life.
For ENIG/ ENEPIG processors serving a diverse group of customers and applications, TWX-40 is a better, proven solution with higher reliability. It saves dollars and processing time, and produces highly consistent results.
TWX-40 is a reduction-assisted immersion gold bath that deposits gold using both immersion and autocatalytic (electroless) reactions. The autocatalytic feature allows the gold to build without attacking the underlying electroless nickel layer. Deposit uniformity is independent of pad sizes and PCB surface geometry, or residual capacitance potential.
The demand for thicker gold is increasingly becoming a requirement for OEM specs, particularly those in the medical, aerospace and “high reliability/harsh environment” sectors. TWX-40 is the first chemistry to enable fabricators to achieve these substantially thicker deposits in one step, at low cost, while preventing nickel corrosion.
TWX-40 gold electrolyte plates directly on electroless palladium or nickel without intermediate activation. Plating speed is 0.12 μm/15 min. at 78°C; the bath exhibits excellent stability and fine geometry edge resolution.
TWX-40 has substantially widened the operating window for wire bonding by facilitating the deposition of thicker gold deposits, while maintaining the integrity of the underlying palladium and nickel. It is broadly recommended for shops working with specifications outside IPC’s gold thickness requirements. Best results are achieved when the bath is used with UIC’s Talon electroless palladium baths as the underlayer for PWBs and IC packages.
For more information click here.
Suggested Items
Absolute EMS Successfully Recertifies ISO 9001:2015 and AS9100 Standards
03/26/2024 | Absolute EMS, Inc.Absolute EMS, Inc., an award-winning EMS provider of turnkey contract manufacturing services, is proud to announce the successful recertification of its ISO 9001:2015 and AS9100 Rev D SAE International Aerospace Standards.
Arlon EMC Receives IPC-4101 QPL Recertification
03/20/2024 | Arlon Electronic MaterialsArlon Electronic Materials has successfully completed an intensive two-day recertification audit by IPC Validation Services that examined Arlon’s manufacturing processes and testing procedures to assure that they are in conformance to the requirements of IPC-4101E-WAM1, the Specification for Base Materials for Rigid and Multilayer Printed Boards.
Northrop Grumman Honors Suppliers for Excellence
03/14/2024 | Northrop GrummanNorthrop Grumman Corporation honored more than 70 suppliers for their outstanding contributions in 2023. In an annual recognition event, the companies included women-, minority- and veteran-owned small businesses as well as those operating in underdeveloped areas.
Cicor Acquires TT Electronics IoT Solutions
03/04/2024 | Cicor Technologies Ltd.The Cicor Group has signed an agreement to acquire TT Electronics IoT Solutions Ltd, with three production sites in the UK and China.
AEM, Texas Aerospace Technologies Bolster Partnership for Latin America
02/26/2024 | AEM Corp.Canadian avionics manufacturer, Anodyne Electronics Manufacturing Corp. (AEM), is pleased to announce a partnership expansion with Texas Aerospace Technologies, a subsidiary of Texas Aerospace Services, to add AEM’s new MTP136D modern panel-mount P25 VHF FM Forest Service radio to its lineup of product offerings for their Latin American customers.