Described is a device having an anti-reflection surface. The device
comprises a silicon substrate with a plurality of silicon spikes formed
on the substrate. A first metallic layer is formed on the silicon spikes
to form the anti-reflection surface. The device further includes an
aperture that extends through the substrate. A second metallic layer is
formed on the substrate. The second metallic layer includes a hole that
is aligned with the aperture. A spacer is attached with the silicon
substrate to provide a gap between an attached sensor apparatus.
Therefore, operating as a Micro-sun sensor, light entering the hole
passes through the aperture to be sensed by the sensor apparatus.
Additionally, light reflected by the sensor apparatus toward the first
side of the silicon substrate is absorbed by the first metallic layer and
silicon spikes and is thereby prevented from being reflected back toward
the sensor apparatus.