REFLECTOR LAYERS - DBRs & HYBRIDS Reflector layers that shine out in LED production • Sputter processes for sensitive substrates and sub layers • Reflectivities close to 100% Relative to the metallic reflectors, so-called hybrids (metal/ dielectric combinations) and Distributed Bragg Relectors “DBRs” (full dielectric stacks) offer near 100% reflectivity, improving device extraction efficiency and light output according to type of LED design. Evatec’s cathode technology on the Radiance platform allow dielectric stacks with the widest reflection band to be deposited accurately and repeatibly. Plasma Emission Monitoring for enhanced layer stoichiometry control and in situ broadband monitoring for precise layer end point termination enable tight process control for film designs with large numbers of layers requiring the greatest accuracy. The Radiance system and process geometry also protects damage and temperature sensitive substrate materials and helps thin film engineers to develop new device designs and materials for the next generation LEDs. Evatec’s hybrid and DBR stack solutions are tailored in cooperation with customers according to: - Substrate material - Wavelength range - Device geometry, angular range - Device packaging
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