High Mobility Conjugated Polymers
Abstract
The performance of all current polymer electronic devices, such as organic field-effect transistors (OFETs), photovoltaic cells, and photodetectors, is limited primarily by the low charge carrier mobilities of current materials. To address this problem this project investigated various polymer semiconductors exhibiting high carrier mobilities and explored their device applications in electronics, optoelectronics, and nanoelectronics. Field-effect electron mobilities as high as 0.1 sq cm/Vs in a spin coated thin films of ladder poly(benzobisimidazobenzophenanthroline) (BBL) were observed. This electron mobility is the highest observed to date in a conjugated polymer semiconductor and was found to vary strongly with intrinsic viscosity (or molecular weight) of the polymer while very stable in air and oxygen. We successfully fabricated and demonstrated a complementary all-polymer inverter for the first time, using p- type poly(3-hexylthiophene) and BBL. A new class of ladder-type bisindoloquinoline semiconductors showing a mobility of 1.0cm fv.s was synthesized. Ambipolar OFETs were achieved from various p- and n-polymer blends. The field-effect mobility of holes in regioregular poly(3-alkylthiophene)s was found to exhibit a non-monotonic dependence on alkyl chain length, showing a maximum mobility with hexyl. Fundamental insights into the structural factors that govern high mobility charge transport and recombination in polymer semiconductors were also achieved.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 20, 2007
- Accession Number
- ADA475466
Entities
People
- Samson A. Jenekhe
Organizations
- University of Washington