NU 2003-071

Inventors

Qinglan Huang

He Yan

Tobin J. Marks

Short Description

A new hole transport system for polymer light emitting diodes

Abstract

Northwestern researchers invented a new hole transport system for polymer light emitting diodes (PLEDs) with negligible visible light absorption, stability to ITO, solvent resistance and tunable electronic properties.  PLEDs are of increasing interest in a wide range of display applications.  However, conventional hole transport layer poly(3,4-ethylenedioxythiophene)-poly(stryenesulfonate) (PEDOT-PSS) devices exhibit significant visible light absorption and ITO interface instability.  By cross-linking siloxane-derivatized hole-transport material (TPD-Si2) with hole transporting or insulating polymers, the investigators address the above limitations.  Further, spin coating a TPD-Si2/TFB blend on ITO with thermal curing not only creates a strongly adherent cross-linked network but further provides an efficient hold transport layer that is stable to subsequent solvent coating operations.

Applications

• Displays: PLED fabrication

Advantages

• Superior PLED performance and efficiency
• Enhanced device life
• Solvent resistance
• ITO interface stability
• Minimal visible light absorption
• Ability to customize specific electronic properties of emissive layer polymer

IP Status

Issued US Patent No. 7,449,509