High Density CVD/PVD Plasmas for SiNOCH coatings (focus on plasma/surface/interface for optical and electrical properties) – HDPlasm-A-SINOCH

Thin films based on oxides, nitrides or carbides, for optics, dielectric properties (SiO, a-SiCO:H) and passivation (a-SiN:H), are used in microelectronics (insulation of contacts) in the field of opto-electronic sensors, or the field of photovoltaïcs. These thin films are mostly produced by plasma decomposition of gas mixtures containing silane or fluorinated or chlorinated derivatives (PACVD) and paradoxically rarely grown by PVD process. Among the factors limiting these two technologies, two aspects appear: i) Silane and its derivatives require the establishment of an important means of security, ii) The use of low- or radio-frequency (35-50 kHz and 13.56 MHz) plasma which, although flexible employment, because of low ionization and dissociation they induce, leads to low deposition rates. These technologies lead to a limitation in the lowering of production costs which are necessary for industrial development. The use of plasma deposition technologies that do not use silane gas and the increasing films growing rates of deposition is an alternative. But these processes and the nature of materials they will achieve (compared to the existing) have to be studied. The use of liquid organosilicon precursors for PACVD, but also the use of high-density plasmas, to increase deposition rates, both in PACVD and reactive PVD technologies (Physical Vapor Deposition), is the alternative we propose; From the materials point of view, thin film type SiNOC:H can replace historical SiNx, SiOx and SiC extending to a wider area their functional properties. Control of atomic composition of these materials can significantly expand the range of variation of the optical index (low index for oxides at low carbon content, high index with high silicon contents) and dielectric characteristics. But the presence of defects in the films near the surface of the substrate or the nature of the interface film/substrate inevitably control optical and electrical properties of the systems. Lack of studies based on understanding the phenomena of film growth, identification and control of film/substrate interfaces considerably limit the development of films extended properties. Acronyme du projet : HD-Plasm-A-SiNOCH. Project HDPlasm-A-SiNOC:H proposes the study and development of high-density plasmas alternative to the existing, that are PACVD of organosilicons [replacement of silane (pyrophoric)] and PVD, of thin film SiNOC:H family materials. It is particularly focused on interactions between plasmas and surfaces, identification, and fundamental role of film/substrate interfaces on the desired properties. This project brings together the expertise of laboratories PROMES-Perpignan, IMN-Nantes, Clermont-LMI and IJL-Nancy. It is kind of industrial research and reflects both areas of process engineering and materials science applications in optics, electronics and PV. It revolves around the following key points: i) Development and characterization of deposition processes using high density plasmas for the development of thin films of SiNOC:H type by PVD and PACVD - Diagnostics of these alternative processes - Contribution from the 'existing, ii) Specific study of plasma/surface interaction in order to identify and control film/substrate interfaces as they determine properties of materials developed - Characterization of materials and their interfaces with treated surfaces - Role of these interfaces, and iii) Identification of performance and applications of SiNOC:H materials for PV applications, opto-electronics and sensors.