Mirror quality and efficiency improvements of reflective spatial light modulators by the use of dielectric coatings and chemical-mechanical polishing.
To date, silicon backplane spatial light modulators have been characterized by poor-quality mirrors. Hillock formation during metal sintering has been identified as the source of this problem. Here hillock elimination is achieved by constraining the metal with a low-temperature plasma-enhanced chemicalvapor deposition silicon dioxide coating. A double-layer metallization procedure increases the silicon area available for circuitry and improves the mirror fill factor. Second-layer metal mirrors require a flat, intermediate dielectric substrate. Chemical-mechanical polishing is demonstrated to provide the flatness necessary to achieve high optical quality.
O'Hara
A
A
Hannah
J R
JR
Underwood
I
I
Vass
D G
DG
Holwill
R J
RJ