IPMS

Fraunhofer Institut Photonische Mikrosysteme

OLED-on-CMOS for Introduction Sensors and Microdisplays Highly efficient, low-voltage organic emitting (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, OLED-on-CMOS technology may also be excellently suitable for various optoelectronic sensor applications by combining Fig. 1: Demonstrator of OLED microdisplay highly efficient emitters, use of low cost materials and cost effective manufacturing together with silicon inherent and CMOS circuitry. Parameters and Specification

Operating Voltage Current The use of OLEDs on CMOS sub- OLED @100 @1000 Efficiency Fraunhofer-Institut strates requires a top emitting, low- Color cd / m² cd / m² @100 cd / m² Photonische Mikrosysteme voltage and highly efficient OLED red 2.4 V 3.1 V 14.1 cd / A Maria-Reiche-Str. 2 structure. By reducing the operating orange 2.5 V 3.2 V 11.6 cd / A 01109 Dresden voltage for the OLED below 5 V, the white 3.2 V 4.7 V 5.7 cd / A Phone: +49 (0) 3 51 / 88 23-0 Fax: +49 (0) 3 51 / 88 23-266 costs for the CMOS process can be www.ipms.fraunhofer.de reduced, because a process without high-voltage option can be used. Contact: Ines Schedwill Phone: +49 (0) 3 51 / 88 23-238 Integrating such OLEDs on a CMOS- • operating temperature [email protected] substrate provides a preferable • electronics feature integration choice for silicon-based optical • sensor co-integration Technical questions: Dr. Uwe Vogel microsystems targeted towards Phone: +49 (0) 3 51 / 88 23-282 optoelectronic sensor applications, [email protected] such as integrated light barriers, Applications optocouplers, sensors, flow sensors or lab-on-chip devices. • microdisplay (viewfinder, projec- tion, HMD, optical inspection,…) • bi-directional microdisplay (in- Challenges cluding optical feedback via internal CMOS sensor) Fraunhofer IPMS reserves the right to change • CMOS-OLED interface (material, • light barriers products and specifications without prior notice. topology, surface characteristics) • opto-coupler This information does not convey any license by • low-voltage operation (<15 V) • optical sensors, e. g. chemical, any implication or otherwise under patents or other right. Application circuits shown, if any, • high brightness medical (fluorescence, photople- are typical examples illustrating the operation (>100…1,000…10,000 cd / m²) thysmography,…) of devices. Fraunhofer IPMS cannot assume • power efficiency • communication (chip-to-chip, responsibility for any problems rising out of the use of these circuits. • lifetime board-to-board, chip-to board,…)

oledcmos-e OLED-on-CMOS for Sensors and Microdisplays

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1,0 Fraunhofer IPMS is the only system red emitter (SRmax=7.93e-3 W/m²*sr*nm; L=81.9 Cd/m²) green emitter (SRmax=2.97e-3 W/m²*sr*nm; L=116.54 Cd/m²) blue emitter (SRmax=47.4e-3 W/m²*sr*nm; L=104.69 Cd/m²) supplier worldwide, who offers 1,0 0,8 product developments starting with 0,9

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green emitter/TiN electrode (V=3.25V; Lmax=108.9 Cd/m²) S 0,1 blue emitter/TiN electreode (V=6.00V; Lmax=477.6 Cd/m²) • R&D in OLED-based integrated 0,0 0,0 0 10 20 30 40 50 60 400 450 500 550 600 650 700 750 800 Viewing angle [°] Wavelength λ [nm] • electronics design (backplane, Fig. 4: Luminance angular characteristic Fig. 5: Spectral characteristics control, interface,…) • system design • product development and quali- fication local hardware information • small to medium volume fabrica- User I/F tion server 10,5 OLEDCam

Blue wireless PD OLED PD OLED PD PD PD PD PD OLED OLG Gateway e.g., UWB, Red Green HS-IrDA OLED PD OLED 3,5 OLED1 Eyepiece PD PD PD PD PD PD PD PD PD PD NIR PD OLED PD OLED2 Fig. 6: Setup of OLED-on-CMOS sensor device Fig. 7: Bidirectional microdisplay for see-through

Fig. 8: OLED microdisplay test chips with varying OLED stacks / colors