SABIC is introducing two new grades in its portfolio of Superflow ULTEM resins that address the trend of electronic component miniaturization to enable smaller, lighter and more-sophisticated devices. Glass fiber-reinforced Superflow ULTEM SF2250EPR and SF2270 resins feature exceptional flow properties for molding burn-in test sockets (BiTS) used to stress-test integrated circuit chips. They can also potentially be used to mold thin-wall, high-precision, miniaturized connectors. Their signature flow properties help meet the challenges of complete mold filling and easy release in ever-smaller components.

Balancing flow with toughness, Superflow ULTEM SF2250EPR and SF2270 resins are excellent alternatives to Source: SABICSource: SABICincumbent materials such as glass fiber-reinforced liquid crystal polymers (LCPs) and polyethersulfone (PES) resins. They deliver greater weld line strength and mechanical performance than LCPs, and higher tensile strength and modulus, higher weld line strength and lower moisture absorption than PES resins.

BiTS manufacturers are seeking new material solutions that can support advanced designs for fine-pitch components that are used under extremely harsh conditions, including high temperatures, high pressures and multiple cycles of use. Superflow ULTEM SF2250EPR resin is an advanced material that can withstand high-heat burn-in tests up to 150° C, while offering higher strength and dimensional stability compared to incumbent materials. South Korea’s Sensata Technologies is one of the first BiTS makers to adopt SABIC’s Superflow ULTEM SF2250EPR resin.

Tommy Oh, design and engineering manager, Sensing Solutions, for Sensata Korea, said, “As the industry advances to finer pitches and miniaturization, existing material solutions present technical limitations in complex BiTS designs due to insufficient flowability and weak weld lines. SABIC’s new Superflow ULTEM SF2250EPR solution enables us to successfully develop and commercialize various BiTS devices with superior performance, especially those with lower pitches, such as 0.5 mm and even 0.4 mm. This material has demonstrated approximately 30% better ductility, plus much better flowability, compared to alternative PES solutions, especially in thinner-wall weld areas. With the new SABIC material, we anticipate major benefits for our BiTS applications in critical performance areas, including tensile and flexural strength.”

Within the ULTEM resin family of polyetherimide (PEI) materials, the Superflow series provides the highest flow properties with up to five times longer flow length than standard glass fiber reinforced ULTEM resins. The high flow performance can reduce the number of gates resulting in less breakage and higher production yields. Other benefits include lower melt temperature settings that can save energy and minimize outgassing, and accelerated cycle times for higher productivity.

Superflow ULTEM resins can potentially replace high-flow, glass fiber-reinforced PES materials. Not only do the ULTEM grades offer similar flow behavior compared to PES — avoiding the need for tool modification — they can deliver up to 20% higher strength and modulus, up to 9% lower density and lower moisture absorption.

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