ELECTROCHROMIC GLAZINGS DE[POSITED BY HIGH RATE PROCESSES

A PROJECT TO DEVELOP VARIABLE SOLAR TRANSMITTANCE COATINGS FOR ARCHITECTURAL GLAZING APPLICATIONS IS PLANNED. THE TRANSMITTANCE MODULATION IS BASED ON THE ELECTROCHROMIC RESPONSE OF TRANSITION METAL OXIDE FILMS, ELECTROCHEMICALLY REDUCED AND OXIDIZED USING LITHIUM ION INSERTION AND EXTRACTION. THE COATINGS WILL BE MULTI-LAYER, THIN FILM STRUCTURES CONTAINING TWO TRANSPARENT ELECTRONICALLY CONDUCTING FILMS, TWO COMPLEMENTARY ELECTROCHROMIC MATERIALS THAT COLOR AND BLEACH SYNCHRONOUSLY DURING OPTICAL SWITCHING, AND AN OXIDE ION CONDUCTING LAYER. ALL LAYERS IN THECOATING ARE METAL OXIDES. THE MATERIALS AND COATING STRUCTURE ARE CHOSEN TO PRODUCE ELECTROCHROMIC GLAZING CAPABLE OF MULTI-CYCLE SWITCHING OVER MANY YEARS UNDER THE HARSH ENVIRONMENTAL CONDITIONS OF GLAZING APPLICATIONS. THE SPECIFIED INNOVATIONS PLANNED ARE THE USE OF MATERIALS AND DEPOSITION PROTOCOLS THAT WILL ALLOW ELECTROCHROMIC COATINGS TO BE DEPOSITED BY SEQUENTIAL DIRECT-CURRENT (DC) MAGNETRON SPUTTERING AT THE HIGH RATES REQUIRED FOR COMMERCIAL VIABILITY IN LARGE COATING OPERATIONS. OF PARTICULAR SIGNIFICANCE ARE INNOVATIONS THAT WILL ALLOW DC SPUTTERING OF LITHIUM ION (LI(+)) CONDUCTING OXIDES AND ELECTROCHROMIC MATERIALS THAT ARE REDUCED IN VACUO WITH THE APPROPRIATE AMOUNT OF LITHIUM FOR ELECTROCHROMIC SWITCHING. THE OBJECTIVES OF THE PHASE I PROJECT ARE THE DEMONSTRATION AND CHARACTERIZATION OF LI(+) CONDUCTING OXIDES DEPOSITED BY REACTIVE DC SPUTTERING AND THE INCORPORATION OF THESE OXIDE FILMS INTO ELECTROCHROMIC DEVICES. THE PHASE II PROJECT WOULD FOCUS ON OPTIMIZATION OF OPTICAL SWITCHING ENVIRONMENTAL STABILITY, AND SCALING TO LARGE AREAS.