Platform Technologies

Absorption spectra for PbS quantum dots in solution
Absorption spectra for PbS quantum dots in solution for a range of quantum dot diameters

Platform technologies are the foundational knowledge and capabilities that enable us to address specific challenges or, in many cases, multiple specific challenges. The list of these platform technologies evolves over time, but not as quickly as the specific applications for which they are used. The following are examples of broad technology areas that we address.

Colloidal Quantum Dots

Colloidal quantum dots are inorganic semiconductors that are synthesized and processed in solution and combine the advantages of organic materials with those of inorganic semiconductors. Unlike traditional bulk inorganic semiconductors, colloidal quantum dots have tunable optical and electronic properties owing to the quantum size effect. We have significant expertise in the fabrication of electronic devices using colloidal quantum dots, which has led to devices that perform on par with those of traditional semiconductors but at a fraction of the cost. These devices include visible and infrared photodiodes, photovoltaic cells, and photosensor arrays. 

Chip-in-flex technology
Demonstration of chip-in-flex technology, with an ultra-thin Si die encapsulated in a polymer package and electrical interconnects

Organic Electronics

Organic electronics use molecular and/or polymeric organic materials that have conductive or semiconducting electrical properties to create electrical devices such as transistors, sensors, or light-emitting devices. The primary advantage of organic semiconductors over traditional inorganic materials such as silicon is that devices can be fabricated at room temperature and over much larger areas. This can lead to lower costs for large devices. We have developed technologies for better devices, component materials, or characterization techniques for organic electronic devices. This includes novel organic light-emitting device architectures, transparent conductors, mechanical test methods, permeation barrier test methods, photovoltaics, and transistors.

Ultra-Flexible CMOS:  Chip-In-Flex

QD-photovoltaic architecture
Cross-sectional drawing of RTI's QD-photovoltaic architecture, as it could be applied to a roll-to-roll manufacturing process

Widespread effort in the last decade has been devoted to developing electronic devices built on flexible substrates. Most of that effort has focused on fabricating devices using organic or inorganic semiconductors that can be processed at low temperatures. In spite of significant progress, these materials rarely match the performance of traditional devices fabricated from single crystal silicon. We have approached this problem differently, investigating the use of high-performance silicon that is made sufficiently thin to make highly flexible chips. Challenges with this approach include maintaining mechanical robustness and electrical integration without sacrificing performance. Our approach is a simple, low-cost process that  provides high-performance functionality for flexible substrates.

Large-Area, Low-Cost, Thin-Film Devices

We have broad expertise and capability in active thin-film devices. These technologies often overlap other projects on which we work, such as the production of hydrogen from sunlight, microelectromechanical systems, or transistors for active matrix displays.