Highly-efficient, low-voltage organic light emitting diodes (OLEDs) are well suitable for post-processing integration onto the top metal layer of CMOS devices. This has been proven for OLED microdisplays so far. Moreover, OLEDon-CMOS technology may also be excellently suitable for various optoelectronic sensor applications by combining highly efficient emitters, use of low-cost materials and cost-effective manufacturing together with silicon-inherent photodetectors and CMOS circuitry. The use of OLEDs on CMOS substrates requires a top-emitting, low-voltage and highly efficient OLED structure. By reducing the operating voltage for the OLED below 5V, the costs for the CMOS process can be reduced, because a process without high-voltage option can be used. Red, orange, white, green and blue OLED-stacks with doped charge transport layers were prepared on different dualmetal layer CMOS test substrates without active transistor area. Afterwards, the different devices were measured and compared with respect to their performance (current, luminance, voltage, luminance dependence on viewing angle, optical outcoupling etc.). Low operating voltages of 2.4V at 100cd/m2 for the red p-i-n type phosphorescent emitting OLED stack, 2.5V at 100cd/m2 for the orange phosphorescent emitting OLED stack and 3.2V at 100cd/m2 for the white fluorescent emitting OLED have been achieved here. Therefore, those OLED stacks are suitable for use in a CMOS process even within a regular 5V process option. Moreover, the operating voltage achieved so far is expected to be reduced further when using different top electrode materials. Integrating such OLEDs on a CMOS-substrate provide a preferable choice for silicon-based optical Microsystems targeted towards optoelectronic sensor applications, as there are integrated light barriers, optocouplers, or lab-onchip devices

First prototypes of bi‐directional OLED microdisplay devices that combine both display and camera functionality on a single CMOS chip (OLED‐on‐CMOS) have been designed. The major goal of this integration is to provide capabilities for eye‐tracking in see‐through HMDs to achieve gaze‐based human–display interaction, e.g., in augmented‐reality applications. The development of the prototype was accompanied by user studies with a simulated bi‐directional microdisplay consisting of a commercially available eye‐tracker and a see‐through HMD. These tests were aimed at providing basic minimum requirements in terms of temporal and spatial resolution of an eye‐tracker to be implemented within the prototype, as well as to evaluate ergonomics of an appropriate user‐interface design. A description of the current state of the hardware architecture and design aspects for bi‐directional OLED microdisplays are also presented.

First prototypes of bi-directional OLED microdisplay devices have been designed, that combine both display and camera functionality on a single CMOS chip (OLED-on-CMOS). Major aim of this integration is to provide capabilities for eye-trackingin see-through HMD to achieve gaze-based human-displayinteraction, e.g. in augmented-reality applications.

Microdisplays are used in various optical devices such as headsets, viewfinders and helmet-mounted displays. The use of organic light emitting diodes (OLEDs) in a microdisplay on silicon substrate provides the opportunity of lower power consumption and higher optical performance compared to other near-to-eye display technologies. Highly efficient, low-voltage, top emitting OLEDs are well suitable for the integration into a CMOS-process. By reducing the operating voltage for the OLEDs below 5V, the costs for the CMOS process can be reduced significantly, because a standard process without high-voltage option can be used. Various OLED stacks on silicon substrate are presented, suitable for full colour (RGB) applications. Red and green emitting phosphorescent OLEDs and blue emitting fluorescent OLEDs all with doped charge transport layers were prepared on a two metal layer CMOS test substrate without active transistor area. Afterwards, the different test displays were meas ured and compared with respect to their performance (current, luminance, voltage, luminance dependence on viewing angle, optical outcoupling etc.)

Organic light-emitting diodes (OLEDs) permit the monolithic integration of microelectronic circuits and light-emitting devices on the same silicon chip. By the use of integrated photodetectors, low-cost CMOS processes and simple packaging; economically produced optoelectronic integrated circuits (OEICs) with combined sensors and actuating elements can be realized. The OLEDs are deposited directly on the top metal layer. The metal layer serves as electrode and defines the bright area. Furthermore, the area below the electrodes can be used for integrated circuits. Due to efficient emitter with low operating voltage it is possible to renounce high-voltage devices depending on selected CMOS process. Thus manufg. cost can be further reduced. Different CMOS metalizations were examd. and their effects on org. light-emitting diodes were analyzed. Red (628nm) and orange (597nm) emitting p-i-n OLEDs with a radiance of 5W/m2sr at 2.8V and 3.0V and a half angle of +-45 Deg were realized on metal layer with low roughness. Near infra-red emitters are in development. We will present an optical microsystem. The functionality of combined sensors and actuating elements as well as advantages and difficulties of the monolithic integration of OLEDs and CMOS will be discussed. The chip was manufd. in a com. 1micro m CMOS technol. The fabricated microsystem combines three different types of sensors: a reflective sensor, a color sensor and a particle flow sensor