NOVEL APPROACH FOR PROCESS CHAMBER COATINGS TO IMPROVE OEE AND REDUCE DEFECTS
Drs. E. Ryabova, N. Wang, M. Shkolnikov, A. Skumanich
SemiCon West Conference, July 12th 2012, San Francisco
An Innovative technology is introduced which improves upon the current chamber protective coatings in semi processing equipment. The novel protective coatings are shown to have several advanced capabilities as well as lower overall costs. The protective coatings are engineered to enable ULSI IC-device manufacturing at and below 22nm design pitch providing two levels of protection for chamber components that eliminates on-wafer defects and for contaminations. High purity fully conformal coatings are applied to the various exposed process chamber parts (shower head, liners, etc.) which can be attacked by the process gases and process environment. The desirable elements for these protective coatings are to withstand this attack and to reduce particle shedding or flaking and metal ion contamination. The key improvements with the novel protective coatings are: lower erosion rates, fully conformal coverage, longer lifetimes between PM's, reduced layer stress, reduced particulate development is anticipated as a result of the key features. In addition, the novel deposition method for the protective coatings allows for: complete coverage of even small features or high-aspect ratio features such as the openings in the shower heads, for improved thermal cycling, and also importantly for lower overall processing costs. The key improvements are: better OEE and overall wafer yield. The talk will outline the deposition approach, provide data on the improved coating functionality, and give an understanding of the cost benefits. A comparison will be made for some key parameters, such as erosion rate, against some standard chamber coatings. The overall implications for improved semi production will be expounded including the reduction in energy and materials for processing, the ability to scale to 450mm, and the enabling elements for the 20nm nodes.
LARGE AREA GLASS COATING FOR ENHANCED PROPERTIES AT LOWER COSTS BASED ON A NON-VACUUM APPROACH
Drs. E. Ryabova, N. Wang, A. Skumanich
9th International conference on Coatings on Glass and Plastics, June 24th, Breda The Netherlands
A novel process is described which improves upon the current approach to coating deposition onto glass by using vacuum coating technologies. This method is achieved without vacuum and at room temperature to apply a range of nanocomposite, clear coatings onto large glass surfaces. The types of coatings include those for scratch and abrasion resistance, as well as other types of compounds, which can be used for anti-reflection (AR) and for Low-e types of films. The technology allows for the application of films over 3 meter square areas with a high throughput that allows for cost effective production implementation. It can be seamlessly integrated into existing glass manufacturing lines. Data will be presented on specific films for scratch and abrasion resistance. Various types of standard measurements are made which include Linear Tabor Abrasion test verified by Haze and Spectral Transmittance measurements, which address the ASTM standards. The results show that the films provide improved coatings with capabilities that meet the functionality requirements. Additional films are developed and discussed which address the AR and Low-e film stack requirements. The general aspects of the novel vacuum-free approach will be outlined and specific data presented. The cost comparisons to standard approaches based on PVD or CVD types of deposition will be highlighted. In addition the advantages as compared with PVD or CVD will be discussed in the context of providing film deposition capability for: large area (2m x 2m and beyond), production scale (more than 1Million sq meters/system/year), and process robustness. Specific superior properties are detailed, and interface engineering capabilities are highlighted for the variety of multilayer stack fabrication in a very economical way.
PROGRESS IN THIN FILM ENCAPSULATION TECHNOLOGY ADVANCED MOISTURE BARRIERS FILMS
Drs. E. Ryabova, A. Skumanich, M. Shkolnikov
PV SEC 26th International Conference Proceedings, September 2011 Hamburg, Germany
Highly scalable disruptive thin film deposition technology is developed and validated based on a modified sol-gel method in response to PV-industry quest for the high quality-low cost methods of fabricating PV-cell structures. This “liquid” based approach is envisioned to replace currently used encapsulants to enable high throughput conveyer type processing of PV-cells with enhanced performance due to the outstanding purity, uniformity and extended light management capability of this method. Solution Derived Nanocomposite (SDN) technology offers an unmatched potential for moisture barrier materials design and engineering in terms of composition and microstructure without using cost prohibitive solutions. Wide variety of layer compounds can be formed, free from residual byproduct intoxication of the cell. SDN encapsulating technology demonstrated the necessary capability to produce protective moisture barrier layer on top of TFPV-structure without compromising its’ as-produced power conversion efficiency. This layer can minimize environmental impact and weathering-caused TFPV-cell performance deterioration. SDN films satisfy the requirements in regard to the damp heat (85/85) test and UV resistance verification, and are lower cost.
LOW COST HIGH PERFORMANCE TCO FILMS- PROCESS INTEGRATION AND RELIABILITY
Drs. E. Ryabova, A. Skumanich, and M. Shkolnikov
IEEE 37th PV SC International Conference Proceedings July 2011 Seattle, WA, USA
The importance of advances in solar cells fabrication has been stressed lately by multiple FiT cuts and abrupt reduction in many other subsidies across the world. The adoption of photovoltaics as a replacement for the fossil fuels however is driven by the threatening to the ecological stability of the planet and has to do with the very existence of humankind. Thin Film Photovoltaics (TFPV) hold a promise to become a contrivance of choice if they will be able to raise numbers for power conversion efficiency complemented by reasonable stability and reliability data. TFPV cell is assembled of several critical layers sandwiched between electrodes, at least one of which has to be transparent. Transparent Conductive Oxides (TCO) play a critical role in PV-cell structure providing incoming passage for the light and outgoing passage for the charge carriers created as a result of conversion. High optical transparency and electrical conductivity are required for the enhanced solar cell performance. Non- defective interface with the under laying film stack is vital for the minimization of loses. Moreover those parameters have to be stable over the extended period of time in order to be practical for the PV-module field installation. Highly efficient technologies (in terms of material cost and utilization rate as well as low capital expenditure and energy consumption) are in demand to build a solar device of required quality and stability at non-prohibitive cost. Non-vacuum low impact technology is developed based on a liquid processing that can provide thin films of excellent purity and precision stoichiometry as well as accommodate conveyer based cells’ manufacturing. Optical, electrical and microstructural properties of these films on glass are tested; as deposited and after exposure to several durability testing methods. Excellent stability is verified in accordance with IEC 61730 and IEC 61215 standard procedures.
NOVEL TCO DEPOSITION TECHNOLOGY FOR IMPROVED PV-CELL PERFORMANCE AT LOWER COST
Drs. E. Ryabova, A. Skumanich, and M. Shkolnikov
PV SEC 25th International Conference Proceedings, September 2010, Valencia
Highly scalable disruptive thin film deposition technology is developed and validated based on a modified sol-gel method in response to PV-industry quest for the high quality-low cost methods of fabricating PV-cell structures. This "liquid" based approach is envisioned to replace currently used vacuum (PVD and CVD) methods to enable high throughput conveyer type processing of PV-cells with enhanced performance due to the outstanding purity, uniformity and extended interface engineering capability of this method. Solution Derived Nanocomposite (SDN) technology offers an unmatched potential for TCO electrode materials design and engineering in terms of composition and microstructure without using cost prohibitive solutions. Wide variety of binary and ternary compounds can be formed at the fraction of cost of vacuum methods. Tunability of optical and electrical properties has a wide process window for example for Al-doped ZnO that is particularly useful for the variety of PV-cells’ architectures. The data presented bellow indicates that SDN provides an enabling technology as a new material for ultra-thin and flexible PV-cell fabrication as well as for the new cell concept implementation.
NOVEL BACK SURFACE FIELD (BSF) STRUCTURE FORMATION BY MODIFIED SOLUTION DERIVED NANOCOMPOSITE (SDN) METHOD FOR LOW COST NEW CELL CONCEPT IMPLEMENTATION
Drs. E. Ryabova, A. Skumanich, and M. Shkolnikov
IEEE 35th PV SC International Conference Proceedings, Honolulu, HI, USA 2010
A novel technology based on a modified hybrid sol-gel technology is presented with PV cell data showing improved performance capability. This "liquid" based approach is envisioned to replace standard Al-BSF with the novel solution based BSF. This latter method can be readily scaled up to the necessary industrial manufacturing levels for c-Si solar cells of virtually any design. Comparative PV test cells were processed and the data show a simultaneous 30% increase in Voc and Jsc accompanied with red shifted spectral IQE graphs using the solution approach. Improved surface passivation is also observed. These results provide the proof-of-concept data. The key advantage is that with this approach, high-quality films with tunable parameters can be generated using low cost, high throughput, non-vacuum processing. Further, various aspects of the materials generated by this approach will enable higher cell performance by providing flexibility in the range of thin film deposition and for extended interface engineering. The approach assists in the progression of the PV roadmap for advanced cell designs envisioned for improved conversion efficiency, as well as for thinner wafers, both of which will impose significant demands and constraints on processing conditions.