Scanning Evaporator Apparatus for Semiconductor Wafer/Substrate and Module Deposition
Original Publication Date: 1988-Jul-01
Included in the Prior Art Database: 2005-Feb-15
This article describes a machine and process system in which a novel scanning evaporation technique is presented which provides for metal evaporation with high throughput and good film quality together with improved oxide step coverage. The scanning action coupled with dynamic feedback of evaporation rate provides excellent uniformity over large substrate areas. The angle of incidence can be controlled by varying aperture size and source-to-aperture distance. Aside from large area uniformity, use of multiple evaporation sources and ion milling, this scanning apparatus is also compact, requiring minimal floor area compared to current evaporation systems. Evaporators generally provide only directional metal deposition, making it very difficult to achieve effective coverage of vertical wall surfaces, e.g., oxide steps.