Sputter-Deposited Low-Emissivity Coatings on Glass

Abstract

IntroductionLow-emissivity (low-E) and solarcontrol coatings increase the energy efficiency of clear float soda-lime-silicate glass for architectural and automotive window applications. At the same time, coated glass largely maintains its neutral color and high visible transmittance. Two major classes of coated products are currently available for the architectural market: The more durable chemicalvapor-deposition (CVD) coatings are deposited on float glass as it is formed. The vacuum deposited low-E coatings, which are the subject of this article, have superior spectral performance and are deposited off-line by the sputter-deposition process. Many elements of this subject have been discussed in the literature, covering energy efficiency for windows, 1 specific examples of low-E coating, 23 a J2 6 brief outline of the deposition techniques, 4 and a more detailed account of optical design considerations for low-E thin-film coatings, particularly for single metal-layer systems. 5 This article briefly discusses aspects of these coatings that relate to their design, performance, and preparation. More attention is given to the materials that constitute the different layers of these coatings and to their specific properties and function.An insulated glass unit (IGU) consists of at least two panes of glass. A spacer and sealants provide mechanical integrity and isolation of the interior space that is filled with a dry gas such as argon or air. A desiccant included within the spacer absorbs the residual moisture and the water vapor that penetrates the sealant. To select the glass panes for optimum energy efficiency, the local climate throughout the year should be taken into account. For example in the colder northern climates, the ideal window will minimize the loss of heat to the outdoors but will allow for passive solar heat gain. On

Low emissivity Ag/Ta/glass multilayer thin films deposited by sputtering

“…1,2 Typical low-e coating structures are transparent dielectric/Ag/dielectric multilayer films. 3 Silver is widely used as the reflectance layer because of its good electrical and optical properties [4][5][6] and has different properties depending on whether the growth is 2-dimensional (2-D) or 3dimensional (3-D). It has been reported that the silver films grew via a 3-D Volmer-Weber mechanism 7 due to poor wettability on metal oxides and were prone to agglomeration at a relatively low temperature.…”

Study on the electrical and optical properties of Ag/Al-doped ZnO coatings deposited by electron beam evaporation

“…There is a report that silver film does not show significant conductivity until its thickness exceeds few nm, e.g. >30 nm, when it becomes continuous and its resistivity decreases with thickness [16][17][18]. However, this thickness of silver film depends on the deposition process and the substrate on which it is deposited [19][20][21].…”

Periodic density fluctuations in sputtered aluminum‐doped silicon oxynitride layers

“…It can be used either as a top coat for mechanical protection or as an intermediate refractive index layer for optimization of the optical performance . Currently, the deposition of Low‐E coatings is mainly performed by magnetron sputtering, a class of physical vapor deposition techniques. In particular, reactive magnetron sputtering is easy to scale‐up, offers low thermal load on the substrate, can be operated with lower environmental impact than chemical vapor deposition, and allows excellent process control, albeit at the expanse of relatively low deposition rates .…”