Chemical Solutions for Wet Deposition
New chemicals are vitally needed to meet the challenging technological requirements of each step of the copper process flow. Through years of intensive research on the copper process field, we have developed a family of sophisticated wet chemical solutions for a wide variety of deposition processes. BASF’s Wet Deposition team serves you with a range of intelligent solutions for your wet deposition processes including Super-filling copper electroplating solutions (Cupur® ECP Series), 3D through-silicon-vias (TSV) solutions (Cupur® TSV Series) and Selective electroless Cu capping layer deposition (Cupur® Capping Series).
The copper metallization step for interconnects uses electrochemical deposition from acidic copper baths. Key factors for effective deposition are: Void-free filling of vias and trenches, smooth surface, low resistance, excellent step coverage, and uniformity across wafer. All these factors are dependent on process parameters, and in particular, the choice of the right chemicals. Our CUPUR® ECP Series VMS and additives such as accelerators and suppressors, result in enhanced copper deposition at the bottom of vias and trenches. Our leveling additives provide a smooth and homogeneous surface for the following chemical mechanical planarization (CMP) process. In-depth understanding of component, as well as surface interactions, are key to developing superior products that meet even the most challenging feature sizes.
3D integration of integrated circuits requires die-to-die interconnection by TSV with high-density, high-aspect-ratio, and through-chip connections. This results in reduced resistive capacitive delay or RC delay, lower power consumption, improved form factor, heterogeneous integration, and lower manufacturing cost. One of the key technologies in 3D chip staking is the electrochemical copper filling of the TSV.
BASF has focused on these critical fill factors. Our CUPUR® TSV Series formulations ensure a fast, void-free, bottom-up electrochemical copper filling process within TSV features, that delivers a minimum over-plating thickness.
BASF has developed the CUPUR® Capping Series of products for selective deposition of conductive metal barriers to encapsulate copper structures. The innovative characteristic of CUPUR® Capping Series is the ability to selectively deposit thin layers of ternary alloys like CoWP and NiMoP on the cop per structures using an electroless process. Advantages of the CUPUR® Capping Series include low processing temperatures, high selectivity, and superior conformal deposition. By using CUPUR® Capping Series solutions, electromigration (EM) lifetime is improved by over ten times compared to standard dielectric caps.