Aram Amassian
Solar and Photovoltaic Engineering Research Center
Division of Physical Sciences and Engineering
Abdullah University of Science and Technology

Solution-Manufacturing of emerging Thin Film Electronics and Photovoltaics

Location: EB1 Room 1011

Friday, October 23rd 2015 - 11:00 am

Solution-processed emerging photovoltaics have seen a dramatic rise in their power conversion efficiency over the past decade, with colloidal quantum dot solar cells now at 10%, organic solar cells at 12%, and hybrid organic-inorganic halide perovskite solar cells rising to 20% at a dizzying pace. Similarly, solution-processed oxide and organic semiconductors have achieved carrier mobilities which far exceed the benchmark mobility of a-Si:H, making these materials suitable for a wide range of emerging electronic and optoelectronic applications. The promise of low-cost pervasive electronics and photovoltaics integrated everywhere in our lives therefore seems to be getting closer to reality in some respects, but significant obstacles remain. Toxicity and stability concerns aside, the success of pervasive electronics and photovoltaics also hedges on our ability to manufacture them with meaningful performance at competitive cost and with high yield on a wide range of substrates and form factors. However, our understanding of solution-manufacturing, underpinned by solution-to-solid phase transformation and thin film growth is in a very nascent state. Case in point, opportunities have existed to solution-print optoelectronic materials (e.g., OLEDs), yet it is predominantly the vacuum-manufacturing route that has prevailed thus far in industry. The maturity gap between solution and vacuum deposition processes, in terms of scientific understanding and engineering therefore has to be bridged. In this presentation, I will summarize our current understanding of thin film formation from solution with emphasis on organic and hybrid perovskite semiconducting materials. Thin film growth from solution and vacuum processes will be compared in order to contrast the significant differences and challenges, but also to highlight the opportunities associated to solution manufacturing. Through practical examples taken from electronics and photovoltaics fields, I will demonstrate how solution processing can be leveraged to make high quality semiconductor thin films, in some instances exhibiting transport properties as good as carefully grown single crystals, and achieve highly efficient solar cells by solution-processing all functional layers, including the active layer, selective contact and electrodes.

Aram Amassian is the SABIC Presidential Chair and associate professor of Materials Science and Engineering at the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia. Aram leads the Organic Electronics and Photovoltaics laboratory and is a member of the Solar and Photovoltaic Engineering Research Centre (SPERC). His research focuses on solution-processing of semiconductor inks - ranging from conjugated molecules and polymers, to colloidal quantum dots, hybrid organic-inorganic perovskites, metal oxides and pseudohalides - for emerging electronic and photovoltaic applications. Aram seeks to establish a quantitative structure-property-performance relationship for semiconducting inks by emphasizing the roles of formulation and processing on phase transformation from solution to solid-state thin films. These lessons are subsequently applied to electronic, optoelectronic and photovoltaic devices. Aram obtained his PhD in Engineering Physics from Ecole Polytechnique de Montreal (Canada) in 2006, and was subsequently a postdoctoral fellow at Cornell University. He was awarded the NSERC (Canada) Postdoctoral Fellowship, as well as the American Vacuum Society's Electronic Materials Postdoctoral Award for his early work in the area of organic electronics and holds the SABIC Chair for his work on solution-processed optoelectronics. He is the author of more than 90 publications and he has been cited >3000 times (Google Scholar), with 1000 citations in 2015 alone.

North Carolina State University