Interface Engineered Organic Thin-Film Transistors

2010 2010

Other formats: Order a copy

Abstract (summary)

Organic thin-film transistor (OTFT)-based electronics performing simple operations/functions offer unique attractions compared to traditional inorganic electronics including lightweight mechanical flexibility and inexpensive large-area coverage and integration. Although speed may be modest versus Si- and inorganic-based circuits, OTFT-based electronics are attractive for diverse new ubiquitous printed electronics applications such as flat-panel displays, sensor arrays, smart cards, and radio-frequency identification (RFID) tags. For OTFTs to be competitive for use in these applications, semiconductor, dielectric, and electrode components should ideally be fabricated via high throughput, low-temperature solution-processing methods such as spin-coating, casting, or printing. In addition, significant performance hurdles must be addressed including, the large operating voltages (>20 V) required to drive moderately complex OTFT circuits, and incompatibilities at material interfaces (organic/organic, organic/metal, and organic/oxide) which strongly influence and in many cases dictate the subsequent device level performance.

Shown here is the development of a series of materials, processes, and device architectures utilizing multifunctional organo-phosphonate self-assembled monolayers (SAMs) which enable low-driving voltage and high electrical performance OTFTs. Rationally designed and integrated SAMs are shown to effectively control the chemical, electrical, and morphological properties at both semiconductor/dielectric and semiconductor/electrode interfaces. These SAM material systems are processed by solution deposition, at low-temperature, in ambient conditions, and are compatible with plastic substrates. The studies presented here are: (1) SAM/high- k metal oxide hybrid gate dielectrics with low-leakage current (-1 nA/cm2) and high capacitance (>400 nF/cm2) providing high-performance OTFTs with driving voltages below 3 V, (2) development of an efficient process for patterning and spin-casting SAM dielectrics on metal oxide activated silicon substrates which enables subsequent fabrication of self-organized patterned solution processed low-voltage OTFTs, and (3) single-component SAMs shown to simultaneously and uniformly modify both metal electrodes and dielectric surfaces to provide desirable interfaces for high-performance bottom-contact OTFTs. Together, these findings represent advancement towards developing low-cost solution processed/printed organic-based electronics.

Indexing (details)

Electrical engineering;
Materials science
0544: Electrical engineering
0794: Materials science
Identifier / keyword
Applied sciences; Dielectrics; Organic transistors; Self-assembled monolayers; Thin film transistors
Interface Engineered Organic Thin-Film Transistors
Acton, Orb
Number of pages
Publication year
Degree date
School code
DAI-B 72/04, Dissertation Abstracts International
Place of publication
Ann Arbor
Country of publication
United States
Jen, Alex V-Y.
University of Washington
University location
United States -- Washington
Source type
Dissertations & Theses
Document type
Dissertation/thesis number
ProQuest document ID
Database copyright ProQuest LLC; ProQuest does not claim copyright in the individual underlying works.
Document URL
Access the complete full text

You can get the full text of this document if it is part of your institution's ProQuest subscription.

Try one of the following:

  • Connect to ProQuest through your library network and search for the document from there.
  • Request the document from your library.
  • Go to the ProQuest login page and enter a ProQuest or My Research username / password.