Progress and Paper report Sept 23, 2009

Progress SPP Manuscript was accepted SPP Manuscript was accepted Evaporation of a multilayer coating with low transmission in the Infrared region A. K. Ang1, P.V. Ramos, M. L. Jamero and I. B. Culaba A. K. Ang1, P.V. Ramos, M. L. Jamero and I. B. Culaba

Introduction 1970’s energy crisis led to research focused on conserving energy 1970’s energy crisis led to research focused on conserving energy German researchers found windows as one of the biggest “heat holes”German researchers found windows as one of the biggest “heat holes” Heat insulating coatings on windowsHeat insulating coatings on windows

Introduction BiOx/Au/BiOx, ZnS/Au/ZnS, glass/BiOx/PbOx/Ag/PbOx/BiOx, TiO2/Ag/ZnO and TiO2/Ag/TiO2 systems BiOx/Au/BiOx, ZnS/Au/ZnS, glass/BiOx/PbOx/Ag/PbOx/BiOx, TiO2/Ag/ZnO and TiO2/Ag/TiO2 systems Silver based systems Silver based systems Lowest thermal transmissionLowest thermal transmission Highest visible light transmissionHighest visible light transmission

Introduction Similar optical properties of Ag, Au, Al, Cu Similar optical properties of Ag, Au, Al, Cu

Design Cr/Cu/Cr on glass substrates Cr/Cu/Cr on glass substrates Cr adhesion layerCr adhesion layer Cu layer as the main mirrorCu layer as the main mirror Third Cr layer for suppression of surface oxidation, preserving its optical propertiesThird Cr layer for suppression of surface oxidation, preserving its optical properties

Methodology 36.5mmx 25.5mmx 1.1mm glass slides 36.5mmx 25.5mmx 1.1mm glass slides Cleaning procedure for glass Cleaning procedure for glass N 2 gasN 2 gas KOH solutionKOH solution KOH + CaCO 3KOH + CaCO 3 HNO 3HNO 3 Distilled waterDistilled water 2-propanol2-propanol Breathe testBreathe test

Methodology Thickness monitorSlides Substrate holder

Methodology Base pressure of torr Base pressure of torr Chromium layers Chromium layers Cr-coated tungsten rod at 90ACr-coated tungsten rod at 90A Copper layers Copper layers Mb dimpled boat at 180AMb dimpled boat at 180A

Methodology Ocean Optics USB-2000 Spectrophotometer Ocean Optics USB-2000 Spectrophotometer 400nm-800nm400nm-800nm Shimadzu IRAffinity 1 FT-IR Spectrophotometer Shimadzu IRAffinity 1 FT-IR Spectrophotometer 2000nm-20000nm2000nm-20000nm 800nm-2000nm 800nm-2000nm No dataNo data

Results and discussions Layer Sample 1 Sample 2 Sample 3 Sample 4 Cr 7.2 nm 6.1 nm 6.8 nm Cu 199 nm nm 98 nm 50.5 nm Cr 8 nm 5.6 nm 7.1 nm 6.3 nm Glass substrate

Results and discussions B A D C 8μm

Results and discussions

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Results and discussions in a study conducted by Hass, the percent reflectance of copper films in the nm region is constant at around 90% [9]. With such high reflectance in this region, the percent transmission is expected to be minimal, which agrees with the data in Fig. 2. in a study conducted by Hass, the percent reflectance of copper films in the nm region is constant at around 90% [9]. With such high reflectance in this region, the percent transmission is expected to be minimal, which agrees with the data in Fig. 2.

Conclusion “Thus Cr/Cu/Cr coatings, having minimal infrared transmission and transmission peaks in the visible region, can be used as a heat insulating system coated on windows” “Thus Cr/Cu/Cr coatings, having minimal infrared transmission and transmission peaks in the visible region, can be used as a heat insulating system coated on windows”

Sample 4 Sample 3 Sample 2 Sample 1 Progress Collected new data in visible regiondata

Progress Also collected data in the visible region using Shimadzu UV PC Spectrophotometer Also collected data in the visible region using Shimadzu UV PC Spectrophotometer Double beam spectrophotometerDouble beam spectrophotometer Data still not retrieved from Chem department PCData still not retrieved from Chem department PC

Progress Performed adhesion test for first 4 samples Performed adhesion test for first 4 samples

Progress Trial 1 (N) Trial 2 (N) Trial 3 (N) Average(N) 200 nm Cu CrCuCr nm Cu CrCuCr nm Cu CrCUCr nm Cu CrCuCr nm Cu Test Cu nm Cu Test Cu nm Cu Test Cu

Progress Progress Fabricated new samples Fabricated new samples Deposition time as basis of film thicknessDeposition time as basis of film thickness 20 sec of Cr deposition at 90 A 20 sec of Cr deposition at 90 A 4 nm/sec x 20 sec = 8 nm Cu deposition at 180 A Cu deposition at 180 A 20, 30, 60, 180 sec samples were already fabricated20, 30, 60, 180 sec samples were already fabricated

Progress Set up for heat insulating tests Set up for heat insulating tests 150W lamp IR thermometer Mask Heat shield Heat absorbing plate

Things to do Test heat shield properties Test heat shield properties Purity test for Cu used in evaporation Purity test for Cu used in evaporation Acquire coated window samples from UPPA Acquire coated window samples from UPPA Compare heat shielding properties of these with Cr/Cu/Cr samples Compare heat shielding properties of these with Cr/Cu/Cr samples