Paper SE+PS-TuM3
Area-selective Deposition by Surface Engineering for Applications in Nanoelectronics. From Blanket to Confined Dimensions

Tuesday, October 23, 2018, 8:40 am, Room 202C

At advanced nodes targeting 10nm feature size and below, lithography starts to dominate costs (EUV, multiple mask passes per layer, pattern placement error). Complementary techniques and materials are needed to continue 2D scaling and extend the Moore’s law. Area-selective atomic layer deposition (AS-ALD) is rapidly gaining interest because of its potential application in self-aligned fabrication schemes for next-generation nanoelectronics. The strong sensitivity of ALD to the chemistry of the surface and its self-limiting nature are particularly appealing. In this talk we report two examples of AS deposition triggered by i) area activation, i.e. a H2-based plasma triggered selective placement of ALD Ru catalyst on SiCN liner with respect to amorphous carbon materials (Fig. 1) followed by AS electroless metal bottom-up deposition and ii) area deactivation by a combination of surface functionalization by molecular self-assembled organic films and ALD of metal oxides and metal nitrides. In the latter case the idea is to chemically and locally bond a molecule directly to the metal surface in order to inhibit reactive sites and then prevent further reactions between the precursor molecules and the surface. A selectivity driven benchmarking of organic passivation films deposited on copper surface from the vapor and liquid phase will be presented, both on blanket surfaces, micron-scale and nanometer-scale patterned features. Two major challanges will be investigated: i) defectivity induced by a reactive ALD process which also nucleates on the part of the surface covered with the organics and metrology; ii) understanding and control of AS ALD material shape at the boundaries between Cu and dielectrics. In Fig.2 the top-down SEM images after AS ALD Hf nitride on 240nm Si oxide/50nm Cu lines are shown. A target thickness of 10nm Hf nitride is deposited by ALD at 120˚C.