Selective Electroless Metallization of Patterned Polymeric Films for Lithography Applications

Abstract

The fabrication of electrical interconnects to provide power for and communication with computers as their component complementary metal oxide semiconductor (CMOS) devices continue to shrink in size presents significant materials and processing compatibility challenges. We describe here our efforts to address these challenges using top-surface imaging and hybrid photoresist/self-assembled monolayer patterning approaches, in conjunction with selective electroless metal deposition, to develop processes capable of fabricating appropriate submicron and nanoscale metal features useful as electrical interconnects, as well as plasma-etch-resistant masks and metal diffusion barriers. Our efforts focus on the development of cost-effective methods compatible with a manufacturing environment that satisfy materials and process constraints associated with CMOS device production. We demonstrate the fabrication of approximately 50-nm-width features in metal with high fidelity and sufficient control of edge acuity to satisfy current industry design rules using our processes and discuss the challenges and opportunities for fabrication of analogous sub-10-nm metal features.

Solution-Based Photo-Patterned Gold Film Formation on Silicon Nitride

“…7 Systematic studies of surface sensitizer preparations have clearly established principles to control the plated film grain size and grain size distribution, and these can be explored for patterning, as well. 23 The degree of infilling shown here is high in the context of low-process-overhead patterned metallization steps, 30 and particularly when targeting suitability for use with structured surfaces incompatible with more involved conventional patterning, such as in enclosed micro-and nanofluidic channels. We developed a solution-based method to form spatially patterned metal features on silicon-rich SiNx thin films.…”

A Photocurable Pd Nanoparticle/Silica Nanoparticle/Acrylic Polymer Hybrid Layer for Direct Electroless Copper Deposition on a Polymer Substrate

“…Hybrid materials composed of polymers and nanoparticles are of great scientific and industrial interest because of their unique properties such as conductivity, sustainability, and permeability [1][2][3][4][5][6]. Efforts have been made to incorporate nanoparticles, such as metal nanoparticles and metal oxide nanoparticles, into polymer matrices, given the fact that a nanoparticle-dispersed polymer material (nanoparticle/polymer hybrid) derives its properties from the nanoparticles, such as catalytic activity [1,2] and optical properties [3,4].…”

“…Efforts have been made to incorporate nanoparticles, such as metal nanoparticles and metal oxide nanoparticles, into polymer matrices, given the fact that a nanoparticle-dispersed polymer material (nanoparticle/polymer hybrid) derives its properties from the nanoparticles, such as catalytic activity [1,2] and optical properties [3,4]. Metal nanoparticle/polymer hybrid films can be prepared by the deposition of metal nanoparticles on the surface of a polymer film and by in situ formation of metal nanoparticles via the reduction of the metal ions by reducing agents [1][2] and photochemically generated radicals [5][6][7][8][9]. Benzoin [6][7][8] and polysilane [9] function as a photo radical initiator to produce metal nanoparticles in solvents and polymer matrices.…”

“…While surface preparation, such as etching to increase the surface roughness, is necessary to provide good adhesion, it can affect the physical properties of the deposited metal film and damage the polymer substrate. Recently, to fabricate a micro pattern such as electric circuits, a simple and cost-effective approach containing direct metallization of photolithographic and printed patterns has attracted much attention [1,2,[12][13][14][15]. Copper is the most important metal in this process, because of its high conductivity and low electromigratory property.…”

Direct Electroless Copper Deposition on A Photolithographic Pattern of Palladium-Nanoparticle/Acrylic-Polymer Hybrid

“…Recently, an alternative approach to the fabrication of the metallic pattern using a combination of photolithography and electroless plating has been reported. [1][2][3][4] Copper is the most important metal for this because of its high conductivity and low electromigratory property. Therefore, we have proposed fabricating the copper micropattern by electroless plating on the pattern formed by photolithography as shown in Fig.…”