Underfill

The same philosophy generally applies to the science of underfills for Flip Chip assembly, though the methods of dispensing and implementing underfills have been evolving. Until recently, the method of achieving underfill coverage has been done reliably through capillary action, but the process is time consuming and therefore costly as a manufacturing process. New “no-flow” fluxing underfills are an advanced Flip Chip assembly process in which the reflow and cure of the solder interconnect and polymer underfill are achieved in concert, and involves the compression flow of the underfill material. Critical parameters include underfill viscosity and concentration.

Depending on the device and the configuration, a no-flow underfill process can increase assembly throughput by nearly fifty percent, particularly in multi-die configurations. The end result is lower manufacturing and product costs, and an added benefit is improved control of underfill voids.

Call Samtec Microelectronics today to find out how your Flip Chip products could be manufactured at Samtec Microelectronics with a “no-flow underfill” assembly flow!

Die Attach & Underfill

Die Attach

Die attach material selection and process implementation play crucial and synergistic roles in any microelectronic assembly; affecting die stress, functionality, thermal management, reliability, and more.  Add a MEMS component and the potential issues are compounded.  Thanks to more than 270 years of development and manufacturing engineering experience among Samtec Micro’s engineering leadership, Samtec Microelectronics takes a systematic approach to process, package, and product development and qualification; designed for “built-in” quality, reliability, and a faster time to market.

Samtec Microelectronics has vast experience with a full range of die attach materials, including: epoxies, polymers, polyimides, thermoplastics, silicones, solders, special low out-gassing, low stress, and anisotropic adhesives.  Available in many forms and with various additives and fillers, Samtec Microelectronics can specify and procure custom formulations to address anticipated production needs.  Adhesive preforms can also be designed and utilized for precise bondline control.

Many of the adhesives are deposited with granular precision and in complex patterns on several automated dispense machines in Samtec Micro’s cleanrooms, all under controlled environmental conditions.  Process monitors for dispensed weight, bondline thickness, and fillet are standard, and die shear and various Failure Mode Analyses are used to validate process and material consistency and production quality.  Adhesive cure methods, outgassing planning and understanding are critical components of die attach material and process selection.