Material Degradation Analysis and Development to Enable Ultra Low Cost, Web-Processed White P-OLED (Phase I)

Investigating Organization
Add-Vision, Inc.

Principal Investigator(s)
J. Devin MacKenzie

Subcontractor
None

Funding Source
Small Business Innovation R&D, Phase I

Award
DOE Share: $98,855

Contract Period
6/20/07 - 3/19/08

Add-Vision (“AVI”) has developed a path for specialty SSL using a doped Polymer Light-Emitting Diode (POLED) device structure, enabling printing of devices with low capital equipment and operating costs.  Devices made with AVI’s approach are efficient, thin, flexible, and robust and AVI has plans with licensing partners to commercialize this technology in entry level specialty SSL applications.  However, additional performance improvements, which would be made possible through the degradation analysis and material and process development proposed in the early stages of this STTR program, would enable commercialization of this technology in a broader range of applications of interest to DOE and their licensees for interior buildings, safety and night lighting.

AVI will combine its expertise in printed POLED devices, materials, processing and electrical characterization with the materials analysis and synthetic capabilities of Lawrence Berkeley National Laboratory to identify the primary efficiency degradation mechanisms for doped POLED devices (Phase-I), then develop a next generation materials set based on this analysis for high efficiency, longer lifetime printed devices.  Upon achievement of the performance and lifetime improvements, Phase-II and III emphasize product demonstration, process scale-up and pilot manufacture with continuous engagement with their manufacturing licensee(s) and product development customers.

AVI’s POLEDs are anticipated to accelerate the early adoption of POLED technology in SSL and improve energy savings and overall product performance in future building applications, including electronic signage, architectural lighting, safety lighting, emergency and portable lighting, and other specialty lighting products.  The print-based manufacturing approach of this OLED technology has inherently low cost capital equipment and operating adoption, product start-up, and large scale web manufacture of SSL that could leverage the resources of the U. S.’s more than 40,000 printing operations.

Since the beginning of the project, Add-Vision has seen substantial improvements in device performance through morphology improvements, formulation optimization of LEP materials, and improved encapsulation technology.  We have now repeatedly demonstrated fully air printed P-OLED devices of >1000 hrs lifetime with 100 Cd/m2 maximum luminance, meeting our initial brightness lifetime goals.  Work is ongoing to improve operating voltages and further elucidate the next limiting degradation issue.  This includes ongoing work with purified organic materials and microscopy work made available by LBNL.

(a)

(b)

Figure 1. (a)  Atomic force micrographs showing the improvements in surface morphology that have been achieved through printed LEP formulations development [right] as compared to the previous formulations [left] Note that the X and Y scales are 8 microns and the z height scales are 40nm per division on the left and 20 nm per division on the right.   The lifetime test data for an encapsulated part made from these formulations is shown in (b) demonstrating 1000 hrs operation in air under constant current driving conditions.

Content dated 2/08