Preparation And Performance Of WO₃Thin Film Electrochromic Device

Electrochromis m means the materia l colour have a reversible change underan externa l electric fie ld. WO3is one of the most important electrochro mic andexcelle nt e lectrochemica l materia ls. WO3thin film is applied extens ive lybecause of its large scale of transmittance, excellent reversib ility, low cost,more recycling times and nontoxic ity.The pure tungsten of99.9%was used as target. WO3thin films weredeposited on glass substrates by RF reactive magnetron sputtering. The ratio ofO2to Ar was5sccm:25sccm,and the sputtering pressure was1.5Pa. All samp leswere annealed at400℃for60min under Ar ambie nce. The influences ofdiffere nt input power on the properties, phase compositions and mor pho logies ofWO3thin films were investigated.Ceramic Al-doped ZnO(AZO) targets were sintered by Al2O3, ZnO mixedpowder.AZO thin films were deposited on glass substrates by RF magnetronsputtering. The influences of pressure, sputtering power and annea lingtemperature on the photoelectric property of AZO thin films were investigated.The best process parameters of RF magnetron sputtering are0.5Pa sputteringpressure,120W RF sputtering power and0sccm:25sccm ratio of O2: Ar. Afterannea ling at400℃for60minutes under Ar ambie nces, AZO thin film shows thebetter structure and photoelectric properties. The AZO thin film has a lowerresistivity of7.88×10-4Ω·cm. Energy efficiency performance of AZO thin filmsis stud ied too.Ceramic LLTO targets were sintered by Li2CO3,TiO2and La2O3powder.LLTO thin films were deposited o by RF magnetro n sputtering and the ionicconductivity of LLTO thin film was tested.WO3thin films were deposited on ITO substrates by RF reactive magnetronsputtering and AZO thin film was used for the transparent conducting la yer.WO3electrochromic device was prepared and tested. The result ind icates thatelectrochromic property of WO3thin films is the best when the sputtering poweris100W firstly the n70W.AZO/Al2O3/AZO energy conserving thin films were designed and depositedon glass substrates. The near infrared (700nm-2500nm) trans mittance of AZO/Al2O3/AZO energy conserving thin film is lower than that o f glass. TheAZO/Al2O3/AZO energy conserving thin film has a highest reflecta nce at1100nm, the reflectance is32%.