Atomic layer deposition (ALD) and atomic layer etching (ALE) are transforming the way semiconductors are built—layer by layer, atom by atom. These atomic-scale processes are essential to scaling future transistors, improving memory, and enabling next-generation device architectures.SEMI spoke with Sergei Ivanov, Business Technology Director of Metallics R D and Balaji Kannan, Business Technology Director of Dielectrics R D and from Merck KGaA, Darmstadt, Germany to learn about their latest material innovations. At the company’s Electronics business, materials scientists and process engineers are advancing atomic-scale engineering to address some of the semiconductor industry’s toughest challenges. From novel deposition chemistries to next-generation etch techniques, their work is helping to enable future logic, memory, and specialty devices.Pushing the Boundaries of ALD Precursor ChemistryAtomic Layer Deposition (ALD) remains a cornerstone technology for scaling transistors and enabling new architectures. Materials scientists at Merck KGaA, Darmstadt, Germany are exploring novel precursors that enhance film quality, streamline processes, and expand the operational window for complex structures:One area of focus is next-generation hafnium and zirconium precursors. “These advanced high-k dielectrics offer better thermal stability, improved step coverage, and reduced impurities while achieving higher k-values,” Sergei Ivanov explained. “Such attributes are essential for logic and memory devices that demand reliable dielectric performance with minimal defect density.”Another important development is area selective deposition (ASD). Merck KGaA, Darmstadt, Germany’s small-molecule inhibitor solutions reduce the need for advanced patterning in narrow dimensions and 3D geometries, enabling cost-effective and simpler integration for leading-edge nodes. Their selective co-reactants platform leverages digitalization techniques including multivariate analysis, digital twin technology, and machine learning to accelerate process development for critical ASD applications. This approach facilitated industry-first adoption of ASD in high volume manufacturing and enables an ever-expanding toolbox of OEM processes for ASD of high-k, Ti, Mo, Si and other thin films.Merck KGaA, Darmstadt, Germany is also broadening the scope of ALD chemistries across the periodic table. “As our customers encounter new technical challenges, we continue to expand our R D scope across new elements and ligands. Examples include europium, lanthanum, scandium, and cerium dopants with improved electrical properties, niobium and vanadium precursors for deposition of nitride and oxide films with reduced impurities and improved ALD performance, and high-performance nickel MILC solutions are finding their way out of our labs and into customer roadmaps at an ever-accelerating pace,” said Sergei Ivanov.The company’s role in molybdenum chemistry is another example. Merck KGaA, Darmstadt, Germany is a key producer of molybdenum precursors including MoO2Cl2 with industry-leading quality, density, and container utilization. The company offers MoCl5 with advanced trace impurity control paired with innovative container technology. The company’s next-generation organic metallic molybdenum precursors incorporate novel ligands that contribute to critical gains in device performance.Merck KGaA, Darmstadt, Germany’s work with organosilane precursors is also opening new possibilities. “For gate-all-around (GAA) transistor technology, precursors incorporating novel bonding structures enable highly conformal dielectric films with excellent electrical and physical properties, even in complex 3D geometries. At the same time, organosilane chemistries designed to increase silicon incorporation during deposition are supporting high-growth-rate oxides for gapfill applications, delivering the thick films required with greater throughput,” said Balaji Kannan. “Together, these innovations highlight how tailored precursor design can address both scaling challenges and manufacturability in next-generation devices.” Driving Selective and Sustainable Atomic Layer Etching (ALE)“Precision in etching is as critical as deposition. Our innovations in ALE are designed to provide ultra-selective, low-damage material removal, which is increasingly vital as device geometries become finer and more complex,” Sergei Ivanov shared. One example is metal-free ligand exchange ALE for high-k materials, where Merck KGaA, Darmstadt, Germany’s research into etching HfO₂, ZrO₂, and HfZrO₄ showcases a novel metal-free approach. This technique enables accurate and damage-minimized etching of high-k dielectrics, which is essential for integrating advanced transistors and memory stacks.These advancements address industry-wide concerns regarding pattern fidelity, material selectivity, and plasma-induced damage, ensuring greater process control and extending the lifetimes of devices.Looking AheadMerck KGaA, Darmstadt, Germany’s strategic commitment to semiconductor innovation includes ongoing R D efforts that reflect the vision of its Electronics business: providing material-centric solutions to the industry’s most complex integration and performance challenges. Whether advancing front-end device scaling or developing breakthrough materials for emerging applications, the Electronics business of Merck KGaA, Darmstadt, Germany is committed to shaping the materials roadmap for a more connected, intelligent, and efficient world.James Lam is Business Development Manager at SEMI Europe.
