Besides the standard substrate glass, Organic Light Emitting Diodes (OLEDs) are suited for the integration on different application-specific materials, like silicon wafers. For the first time ever, this allows the monolithic integration of highly efficient light sources into standard CMOS Integrated Circuits.

Due to the combination of OLEDs with CMOS technology (OLED-on-CMOS) advantages concerning light-brightness, efficiency, low operating voltage and spectral characteristics can be achieved. This offers a great variety of completely new applications regarding the possibilities of the integration of different sensor-devices (e. g. photo detectors) into the CMOS-circuit-technology. In addition to the advantage of the supplement of efficient and stable light-emitting devices on the CMOS-chip, using the OLED-on-CMOS-technology, CMOS-based activation and signal processing can be realized. Since the light-emitter can be placed above the CMOS-electronics, no additional valuable space on the chip is claimed. This combination allows the production and application of highly developed devices: first of all, OLED-microdisplays (based on CMOS-technology) with embedded image-receiver (bi-directional microdisplay) for an interactive adaption and control of the displayed information via eye movement and, secondly, optoelectronic sensors with an integrated light source. Since a while the Fraunhofer IPMS offers developments in this field and is able to present different technology-demonstrators.

During the Photonics West 2009 the Fraunhofer IPMS will present the prototype of a bi-directional OLED microdisplay with an imaging CMOS photo diode matrix interlaced in a QVGA display (12 x 9 mm²), both are integrated and work at the CMOS chip. Furthermore, an optical flux sensor will be presented, which includes the required light source on the CMOS-sensor chip.

A CMOS photo diode line allows the detection of the speed of a particle flow and an embedded OLED light source in the form of stripes in parallel to the photo diode line provides the illumination of the medium. Due to the achieved reduction of the expenditure regarding the construction and circuit technology numerous applications of those devices are enabled. Fields of application vary from chemistry, medicine to life science. Other applications of OLED-on-CMOS include light barriers, opto-couplers and optical communications.