Project TitleNovel Intercalated Superlattices with Modulating Dielectric Properties
Track Code2005-092
Short Description

A family of intercalated metal oxide self-assembled superlattice dielectrics providing extraordinary insulative and capacitance properties for thin film transistor and organic electronic devices.

#materials #semiconductor #thinfilm


Northwestern researchers have developed a family of unique thin film dielectrics with extraordinary capacitance suitable for a wide range of electronic applications. This invention demonstrates the intercalation of metal oxides into self-assembled superlattices (SASs) which efficiently modulates the dielectric properties of the SAS dielectric. The resulting films may be easily integrated into OTFT devices and are also applicable to capacitative elements in LC displays, supercapacitors, and other insulated field-effect devices. Integrated circuits (IC) fabricated from organic thin film transistors (OTFTs) offer the potential of cheap, logic circuits with diverse electronic applications as diverse. High-mobility, stable, and solution-processable organic semiconductor materials including both p-type (hole-transporting) and n-type (electron-transporting) semiconductors on SiO2 and plastic substrates have undergone significant advances for OTFT applications. However, there remains a need for alternative insulator materials in order to significantly reduce the OTFT operating voltage. Thus, while the carrier mobilities of organic semiconductors now rival those of amorphous Si, this is generally achieved at very large source-drain/source-gate bias (30-50V) and incurs excessive power consumption. This family of new dielectrics increases the capacitance of the gate dielectric but at the low-cost/low-capital investment manufacture anticipated for organic electronics. Further, this dielectric/insulating SAS film technology demonstrates excellent dielectric properties in metal-insulator-semiconductor (MIS) and OTFT devices. The thin SAS films of about 9nm reduce leakage currents by about 9 orders of magnitude (~10-9 A/cm2). In addition, the SAS-based FET exhibits comparable mobility as those with conventional 300 nm-thick SiO2 insulators (about 0.1 cm2/Vs), but they have the additional advantage of exhibiting about two orders of magnitude reduction in operational voltage, essential to reduce OFET device power dissipation and enable high frequency operation.

TagsMATERIALS: semiconductor, MATERIALS: thin film
Posted DateJun 30, 2011 6:16 PM


Tobin J Marks*

Antonio Facchetti 


Electronics (e.g. electronic price tags, postage stamps, RFID tags, and "smart" cards)


• Significant reduction in operational voltage
• Comparable carrier mobility as SAS-based dielectrics
• Significant reduction in leakage currents compared to Si/SiO2 native oxide substrates

IP Status

Contact Information

Zach Brown, PhD
Invention Associate  
(p) 847.491.4629