PME Industry Seminar Series - Dr. Rudy Wojtecki

Reactive Inhibitors for Area Selective Depositions

Area selective depositions (ASD) take advantage of the chemical contrast between material surfaces in device fabrication, where it is used to grow a film by a chemical vapor deposition process on one portion of the pattern – such as a metal surface versus a dielectric. This type of self-aligned process can be applied to a variety of nanofabrication schemes to, for instance, improve device tolerance to lithography alignment errors or to reduce interconnect resistance for device performance improvements. While ASD can be accessed through a variety of methods – differences in native surface reactivities between materials, self-assembled monolayers (SAMs), and small molecule inhibitors, to name a few – our group is exploring the use of reactive organic inhibitors in ASD processes. While these SAM chemistries require solution-based coating methods, the concept of a cross-linkable inhibitor was translated to a vapor phase process, demonstrated with propargyl amine to achieve a selective TaN deposition at 300°C. To tailor inhibitor thickness, chemically reactive surfaces were exploited where monomers were selectively attached to a metal surface and then activated, and polymers grown in an area selective manner with tailorable thicknesses. This tailorable thickness presents several advantages over monolayers – such as enabling ASD on patterns with topography or the control of lateral overgrowth.