Sensor sees vertical color

A team of German and US scientists say they have made the first large-area (512 × 512) color sensor free of aliasing effects by stacking red, green, and blue imaging elements. The researchers come from the International University Bremen (Bremen, Germany; www.iu-bremen.de), Research Center Jülich (Jülich, Germany; www.fz-juelich.de), and the Palo Alto Research Center (Palo Alto, CA, USA; www.parc.xerox.com).

Rather than placing RGB filters over three separate pixels to render a single color pixel, the researchers have vertically integrated RGB thin-film layers consisting of amorphous silicon and its alloys. The spectral sensitivity of the sensors is controlled by the optical properties of the materials and applied bias voltage. Obvious applications include lab-on-chip systems, and the researchers are hoping to work with CMOS manufacturers to put the sensors on top of CMOS readout electronics for camera applications.