Embedded systems are marked by a need for small components, unmatched reliability, and the ability to withstand harsh conditions. Transcend Information offers corner bond as a customization option for its embedded products to increase reliability under high thermal or vibratory stress, high gravitational acceleration, and high fatigue cycle applications.
How corner bond works
Transcend's corner bond is an economic bonding solution of applying fluid encapsulant or liquid epoxy around the perimeter of a silicon chip, leaving just one gap unapplied. This is to allow space for future thermal expansion. The corner bond adhesive is then cured with UV light to form a structural bond between the silicon chip and the PCB.
Corner bond is commonly used for ball grid array (BGA) based storage for applications such as handheld devices, which must pass drop or tumble tests.
When a BGA device is exposed to repeated heating and cooling cycles, a BGA chip will expand or contract at a different rate than that of the underlying substrate, due to the difference in each material's coefficient of thermal expansion. This differential creates mechanical stress on the device's solder joints.
Corner bond is used as a stress relieving agent, evenly distributing the expansion and contraction effects. By spreading stresses throughout the chip and PCB interface with a mechanical bond, less stress is concentrated on the solder joints, increasing device reliability.
From using in-house dispensing machines, to performing meticulous drop tests on all bonded products, Transcend implements corner bond technology to PCIe M.2 SSDs as built-in feature for the best quality and longevity. Customization is available upon customer request. We also implement another technology - underfill - to enhance reliability. Click here to know more.