Thomas Rembert and Ali Javey

EECS Department, University of California, Berkeley

Technical Report No. UCB/EECS-2015-148

May 18, 2015

In this report, a room temperature cathodic arc deposition technique to produce nanocrystalline ZnO thin films for low voltage thin film transistors (TFTs) and digital logic inverters is presented. Room-temperature deposited ZnO films exhibit high Hall mobilities exceeding 21 cm2V-1s-1. All-oxide fully transparent ZnO-channel TFTs were realized on alkali-free glass and flexible polyimide foil. Devices exhibited subthreshold swings as low as 204 mV/dec, saturation mobilities as high as µsat = 3.1 cm^2/Vs, threshold voltages between Vt = 0.36-1.2 V, and on/off current ratios of 10^5, all while operating at ±3 V. Bending studies were performed on the ZnO TFTs on polyimide, displaying retention of its original performance characteristics while bent at r = 8 mm. The all-oxide inverter is fabricated on polyimide and operates at 2 V, exhibiting a peak gain of ~ 8. The work presents a practical materials and device platform for low-temperature fabrication of TFTs with high performance on virtually any substrate.

Advisors: Ali Javey

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BibTeX citation:

@mastersthesis{Rembert:EECS-2015-148,
    Author= {Rembert, Thomas and Javey, Ali},
    Title= {Room temperature approach to fully transparent, all-oxide thin-film transistors},
    School= {EECS Department, University of California, Berkeley},
    Year= {2015},
    Month= {May},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2015/EECS-2015-148.html},
    Number= {UCB/EECS-2015-148},
    Abstract= {In this report, a room temperature cathodic arc deposition technique to produce nanocrystalline ZnO thin films for low voltage thin film transistors (TFTs) and digital logic inverters is presented. Room-temperature deposited ZnO films exhibit high Hall mobilities exceeding 21 cm2V-1s-1. All-oxide fully transparent ZnO-channel TFTs were realized on alkali-free glass and flexible polyimide foil. Devices exhibited subthreshold swings as low as 204 mV/dec, saturation mobilities as high as µsat = 3.1 cm^2/Vs, threshold voltages between Vt = 0.36-1.2 V, and on/off current ratios of 10^5, all while operating at ±3 V. Bending studies were performed on the ZnO TFTs on polyimide, displaying retention of its original performance characteristics while bent at r = 8 mm. The all-oxide inverter is fabricated on polyimide and operates at 2 V, exhibiting a peak gain of ~ 8. The work presents a practical materials and device platform for low-temperature fabrication of TFTs with high performance on virtually any substrate.},
}

EndNote citation:

%0 Thesis
%A Rembert, Thomas 
%A Javey, Ali 
%T Room temperature approach to fully transparent, all-oxide thin-film transistors
%I EECS Department, University of California, Berkeley
%D 2015
%8 May 18
%@ UCB/EECS-2015-148
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/2015/EECS-2015-148.html
%F Rembert:EECS-2015-148