Evaluation of the field-effect carrier mobility in single-grain (and polycrystalline) organic semconductors

H. L. Kwok

doi:10.1117/12.611395

15 September 2005 Evaluation of the field-effect carrier mobility in single-grain (and polycrystalline) organic semconductors

H. L. Kwok

Author Affiliations +

Proceedings Volume 5924, Complex Mediums VI: Light and Complexity; 59240P (2005) https://doi.org/10.1117/12.611395
Event: Optics and Photonics 2005, 2005, San Diego, California, United States

Abstract

Mobility in single-grain and polycrystalline organic field-effect transistors (OFETs) is of interest because it affects the performance of these devices. While reasonable values of the hole mobility has been measured in pentacene OFETs, relatively speaking, our understanding of the detailed transport mechanisms is somewhat weak and there is a lack of precise knowledge on the effects of the materials parameters such as the site spacing, the localization length, the rms width of the density of states (DOS), the escape frequency, etc. This work attempts to analyze the materials parameters of pentacene OFETs extracted from data reported in the literature. In this work, we developed a model for the mobility parameter from first principle and extracted the relevant materials parameters. According to our analyses, the transport mechanisms in the OFETs are fairly complex and the electrical properties are dominated by the properties of the trap states. As observed, the single-grain OFETs having smaller values of the rms widths of the DOS (in comparison with the polycrystalline OFETs) also had higher hole mobilities. Our results showed that increasing the gate bias could have a similar but smaller effect. Potentially, increasing the escape frequency is a more effective way to raise the hole mobility and this parameter appears to be affected by changes in the molecular structure and in the degree of "disorder".

Citation Download Citation

H. L. Kwok "Evaluation of the field-effect carrier mobility in single-grain (and polycrystalline) organic semconductors", Proc. SPIE 5924, Complex Mediums VI: Light and Complexity, 59240P (15 September 2005); https://doi.org/10.1117/12.611395

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available