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Research paper : The aerosol deposition method (J. Akedo et al.)−124 Synthesiology - English edition Vol.1 No.2 (2008) the NEDO Project, aluminum nitride thin plate was replaced with ceramic coating on a metal jacket using the AD method, and the improvement in performance and energy consumption reduction throughout the entire manufacturing phase were investigated. By replacing the insulation layer with AD coating, thickness was reduced to 1/10 or less, adsorption per applied voltage increased about 20 times, and heat conductivity and speed of adsorption response to a metal jacket also increased dramatically. Since heat conductivity can be improved by replacing aluminum nitride with other materials, ex. yttria, new functional improvements such as increasing corrosion resistance against plasma can be expected.For the manufacturing of electrostatic chuck through introduction of the AD method, approximately 80 % reduction in energy consumption could be achieved for the entire manufacturing process, as shown in Figure 4. The manufacturing process time was also reduced to 1/10 or less. For this particular application, the energy reduction was obtained not only by the removal of sintering process that is required in conventional manufacturing to be performed at high temperatures, but also for further removal of other fabrication process steps present in the conventional manufacturing process. Particularly, the reduction in energy consumption of polishing process needed to gain evenness of adsorption surface, which determines the performance of electrostatic chuck, contributed greatly to the reduction of total energy consumption. When ceramic thin plate is made using conventional ceramic process, there is substantial contraction and warping during firing, and energy consumption needed for planarization is quite substantial. Using ceramic coating by the AD method, sufficient pressure resistance can be obtained since the film is dense even if it is thin, and warping of adsorption surface is greatly reduced because of its thinness. The energy reduction in manufacturing process is relevant to mass production design, and we believe that the efficacy of the AD method in energy conservation should be further investigated.Although the above case study was for the particular case of electrostatic chuck, energy conservation can be achieved by employing AD method in ceramic coating in many other ceramic products, when ceramics with properties such as corrosion resistance, insulation, and hardness are demanded.Improvement of resistance to plasma corrosion by using yttria film coated using the AD method in inner walls of chamber and components in semiconductor manufacturing device is currently in the process of commercialization. Because by using CVD, separate devices are needed for each material and/or process step, an alternative method using a single device needs to be investigated. It may eventually become possible to optimize scale, facility cost, and energy consumption of semiconductor manufacturing plant according to production volume.4 Possibility of lower cost and energy conservation by application to MEMS optical scanner4.1 Application to Si-MEMS scanner and simplification of processFig. 4 Structure of electrostatic chuck and comparison of energy consumption in manufacturing process using AD method.CompositionFiring method (conventional method)AD methodCharacteristic of AD methodProcessPowder preparationSubstrate creationFiringCoatingDot coatingPlatingGrindingPolishingPolishingInspectionInspectionSurface treatmentJacket bondingGreen sheet productionPrintingLaminationRaw processing1000 °C or moreFiringRemoval from furnace1~2 weeksEnergy consumed: 7500 kWhEnergy consumed: 1300 kWhFiring2250 kWh750 kWh750 kWhGrinding3750 kWh700 kWh 300 kWhPolishingCoatingPowder preparation300 kWhCoating at room temperature・No heating of substrate・No heating of powderNo heavy metal contamination of wafer since it is 100 % alumina.Compared to conventional firing process, AD coating process shows 82 % reduction in energy consumption (7500 kWh → 1300 kWh) and 96 % reduction in time (288 hrs → 10 hrs).Alumina, titania, chromiaInternal electrodeElectrostatic chuckChuck100 % aluminaAD filmCooling plateIndium bondCooling plateCooling jacket (aluminum alloy)Cooling jacket (aluminum alloy)Cooling platePowder preparation ~ Raw processing Surface treatment ~ Bonding Excellent heat conductivity since it is thin ceramic coated film.Powder preparation(52)−

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