WelcoTM AP520: Water Soluble Paste for Fine-Pitch Component and Flip Chip Attach in System-in-Package Applications

The semiconductor advanced packaging industry and related technologies serve the need of fast-evolving and increasingly complex electronic products used in 5G communications, Internet of Things, AR and smart wearables, electric vehicles, and other consumer or industrial applications. As constantly driven by higher performance and smaller form factors, the number of components in semiconductor packages such as the system-in-package (SiP) continue to increase while the package size decreases. To meet the demand of today’s electronic industry, solder materials that can create tiny and reliable joints with close to zero defects are needed.

Heraeus’ new WelcoTM AP520 is a state-of-the-art water-soluble type 7 printing paste designed to address these challenges. With excellent paste release down to 90 µm pitch (55 µm stencil opening and 35 µm line spacing), no splashing and best-in-class low void performance, AP520 makes an excellent choice for fine pitch components and flip chip attach for next generation System-in-Package applications. In addition, WelcoTM AP520 T7 solder paste makes all-in-one printing for flip chip and SMD pads possible. This simplifies SiP assembly processing steps, reduces CAPEX and material costs, and at the same time, eliminates defects such as incomplete soldering due to substrate warpage and/ or uneven placement of flip chips.

Key Features

  • Uses high-quality Welco™ T7 powders
  • Consistent paste release down to 90um pitch
  • Pure DI water cleanable
  • Best-in-class low voids
  • No splashing or beading
  • Enables all-in-one printing of passive components and flip chips in a single step