Initiated PECVD of Organosilicon Coatings: A New Strategy to Enhance Monomer Structure Retention

Abstract

A new deposition method, initiated PECVD (iPECVD), is proposed for the formation of organosilicon polymers with enhanced monomer structure retention compared to conventional PECVD. The quasi‐selective fragmentation of an initiator is driven by a low power plasma discharge, as opposed to using a hot filament for initiator decomposition as in a standard, plasma‐free initiated CVD (iCVD). The weak peroxide bond (OO) in the initiator permits the formation of radical species at very low plasma power density (0.07 W · cm−2). Kinetic analysis of the deposition process indicates that the film formation rate follows the Arrhenius law, similarly to other iCVD process from organosilicon monomers.

Global and local planarization of surface roughness by chemical vapor deposition of organosilicon polymer for barrier applications

“…Details of the iPECVD process can be found in Ref. 17. Figure 1 shows the cross sectional SEM images of the silicon wafer coated with the microspheres without and with a polymer deposited on them at different coating thicknesses.…”

“…17 iPECVD deposition conditions were adopted from previously reported work. The monomer and initiator gases were uniformly distributed across the entire width of the substrate using a distributor tube that was 30 cm long and 1 cm in diameter with ten 1 mm holes.…”

“…iPECVD, similarly to the conventional initiated chemical vapor deposition (iCVD), is based on the decomposition of an initiator molecule to give fragments of the initiator, which then initiate the polymerization. 17,18 In the conventional plasma-free iCVD the initiator is thermally broken by a filament heated up to 250-300 C. In the iPECVD it is broken by a gentle plasma discharge (power density as low as 0.07 W/cm 2 ). In a previous contribution we demonstrate that at such low plasma power density the monomer fragmentation was very limited and the deposition kinetics was largely similar to conventional plasma-free iCVD.…”

Chemical Vapor Deposition for Solvent‐Free Polymerization at Surfaces

“…In particular, iCVD has been used to fi ll the pores of the substrate [ 50 , 51 ] and offers a microscopically fl at surface for the deposition of the subsequent inorganic layer. [ 52 ] A new process, initiated-plasmaenhanced CVD (iPECVD), [ 53 ] yielded liquid-like depositions -a meniscus was observed when the coating was deposited inside a trench (see Figure 3 a i). This type of deposition can be desirable for planarization and pore fi lling.…”

The impact of the nano-pore filling on the performance of organosilicon-based moisture barriers

“…1 shows the comparison between the FT-IR absorption spectra of the i-CVD and PE-CVD layers, normalized by their thickness, together with the liquid V 3 D 3 and TVTSO monomer spectra [39]. The monomer functional groups (namely the Si\ \CH 3 bending absorption band at 1260 cm − 1 [41,42], and the Si\ \O\ \Si asymmetric stretching band, either cyclic at 995 cm − 1 , or linear 1066 cm −1 [43]) are entirely retained in the i-CVD polymer structures, as also shown in Ref. [40], since the vinyl groups are the only units involved in and affected by the polymerization process [41,44,45].…”