Top Interface Engineering of Flexible Oxide Thin‐Film Transistors by Splitting Active Layer

The effect of active layer (amorphous indium–gallium–zinc oxide, a-IGZO) splitting on the performances of back-channel-etched (BCE) and etch-stopper (ES) thin-film transistors (TFTs) on polyimide substrate is studied. While the performance of BCE TFT is independent of active layer splitting, the performance of ES TFT is improved significantly by splitting the active layer into 2–4 µm width along the channel. The saturation mobility is enhanced from 24.3 to 76.8 cm2 V−1 s−1 and this improvement is confirmed by the operation of a ring oscillator made of the split TFTs also. X-ray photoelectron spectroscopy (XPS) analysis of the split a-IGZO indicates the incorporation of F at the island interface and thus improves the top interface quality, leading to a significant improvement of the top channel TFT mobility from 0.25 to 24.22 cm2 V−1 s−1. This improvement is correlated with bonding of In with F at the top interface according to XPS results. The bias stability, hysteresis, and mechanical stability of the ES a-IGZO TFT are also remarkably improved by splitting a-IGZO active layer.

[1]  Yu-Jen Chang,et al.  A General Route to Printable High‐Mobility Transparent Amorphous Oxide Semiconductors , 2007 .

[2]  John A Rogers,et al.  Light Emission Characteristics and Mechanics of Foldable Inorganic Light‐Emitting Diodes , 2010, Advanced materials.

[3]  T. Ma,et al.  Passivation of (111) Si/SiO2 interface by fluorine , 1992 .

[4]  Min Hyuk Choi,et al.  Transparent Flexible Circuits Based on Amorphous-Indium–Gallium–Zinc–Oxide Thin-Film Transistors , 2011, IEEE Electron Device Letters.

[5]  T. Nabatame,et al.  Codoping of zinc and tungsten for practical high-performance amorphous indium-based oxide thin film transistors , 2015 .

[6]  John A Rogers,et al.  Controlled buckling of semiconductor nanoribbons for stretchable electronics , 2006, Nature nanotechnology.

[7]  Yonggang Huang,et al.  Materials and Mechanics for Stretchable Electronics , 2010, Science.

[8]  Jin Jang,et al.  High-Performance Amorphous Indium–Gallium–Zinc–Oxide Thin-Film Transistor With a Self-Aligned Etch Stopper Patterned by Back-Side UV Exposure , 2011, IEEE Electron Device Letters.

[9]  Z. Wang.  Self‐Powered Nanosensors and Nanosystems , 2012, Advanced materials.

[10]  M. Hung,et al.  Highly stable fluorine-passivated In–Ga–Zn–O thin-film transistors under positive gate bias and temperature stress , 2014 .

[11]  U-In Chung,et al.  Amorphous hafnium-indium-zinc oxide semiconductor thin film transistors , 2009 .

[12]  H. Ohta,et al.  Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors , 2004, Nature.

[13]  M. Mativenga,et al.  Fully transparent and rollable electronics. , 2015, ACS applied materials & interfaces.

[14]  Yonggang Huang,et al.  Multifunctional Epidermal Electronics Printed Directly Onto the Skin , 2013, Advanced materials.

[15]  Y. Tai,et al.  Hysteresis of Transistor Characteristics of Amorphous IGZO TFTs Studied by Controlling Measurement Speed , 2015 .

[16]  Jin Jang,et al.  Light/negative bias stress instabilities in indium gallium zinc oxide thin film transistors explained by creation of a double donor , 2012 .

[17]  E. Fortunato,et al.  Amorphous IZO TTFTs with saturation mobilities exceeding 100 cm2/Vs , 2007 .

[18]  Jin Jang,et al.  Effect of top gate potential on bias-stress for dual gate amorphous indium-gallium-zinc-oxide thin film transistor , 2016 .

[19]  Y. Uraoka,et al.  Effect of Fluorine in a Gate Insulator on the Reliability of Indium-Gallium-Zinc Oxide Thin-Film Transistors , 2016 .

[20]  B. Bae,et al.  Solution-Processed Flexible Fluorine-doped Indium Zinc Oxide Thin-Film Transistors Fabricated on Plastic Film at Low Temperature , 2013, Scientific Reports.

[21]  Tae Whan Kim,et al.  Effect of the Ti molar ratio on the electrical characteristics of titanium-indium-zinc-oxide thin-film transistors fabricated by using a solution process , 2011 .

[22]  Hideo Hosono,et al.  Interface and bulk effects for bias—light‐illumination instability in amorphous‐In—Ga—Zn—O thin‐film transistors , 2010 .

[23]  Sheng-Po Chang,et al.  High-Performance a-IGZO Thin-Film Transistor Using $ \hbox{Ta}_{2}\hbox{O}_{5}$ Gate Dielectric , 2010, IEEE Electron Device Letters.

[24]  H. Zan,et al.  Effective Mobility Enhancement by Using Nanometer Dot Doping in Amorphous IGZO Thin‐Film Transistors , 2011, Advanced materials.

[25]  M. Mativenga,et al.  High-Performance Homojunction a-IGZO TFTs With Selectively Defined Low-Resistive a-IGZO Source/Drain Electrodes , 2015, IEEE Transactions on Electron Devices.

[26]  K. Saraswat,et al.  Improvement in High-$k$$(hboxHfO_2/hboxSiO_2)$Reliability by Incorporation of Fluorine , 2006, IEEE Electron Device Letters.

[27]  M. Mativenga,et al.  Highly Robust Neutral Plane Oxide TFTs Withstanding 0.25 mm Bending Radius for Stretchable Electronics , 2016, Scientific Reports.

[28]  M. Tabe,et al.  Segregation and defect termination of fluorine at SiO2/Si interfaces , 1993 .

[29]  Changjung Kim,et al.  Highly Stable Transparent Amorphous Oxide Semiconductor Thin‐Film Transistors Having Double‐Stacked Active Layers , 2010, Advanced materials.

[30]  Min-Koo Han,et al.  Effect of channel widths on negative shift of threshold voltage, including stress-induced hump phenomenon in InGaZnO thin-film transistors under high-gate and drain bias stress , 2012 .

[31]  Sunghwan Lee,et al.  Amorphous IZO-based transparent thin film transistors , 2008 .

[32]  M. Hung,et al.  Suppression of Negative Gate Bias and Illumination Stress Degradation by Fluorine-Passivated In-Ga-Zn-O Thin-Film Transistors , 2016 .

[33]  C. Battaglia,et al.  Room Temperature Oxide Deposition Approach to Fully Transparent, All‐Oxide Thin‐Film Transistors , 2015, Advanced materials.

[34]  Yong-Hoon Kim,et al.  Highly Stable and Imperceptible Electronics Utilizing Photoactivated Heterogeneous Sol‐Gel Metal–Oxide Dielectrics and Semiconductors , 2015, Advanced materials.

[35]  Jeonghyun Kim,et al.  An Epidermal Stimulation and Sensing Platform for Sensorimotor Prosthetic Control, Management of Lower Back Exertion, and Electrical Muscle Activation , 2016, Advanced materials.

[36]  Jonathan A. Fan,et al.  Materials and Designs for Wireless Epidermal Sensors of Hydration and Strain , 2014 .

[37]  Jin Jang,et al.  Time-temperature dependence of positive gate bias stress and recovery in amorphous indium-gallium-zinc-oxide thin-film-transistors , 2011 .

[38]  John F. Wager,et al.  Negative bias illumination stress assessment of indium gallium zinc oxide thin‐film transistors , 2015 .

[39]  M. Mativenga,et al.  High current stress effects in amorphous-InGaZnO4 thin-film transistors , 2013 .

[40]  H. Meng,et al.  Achieving High Field‐Effect Mobility in Amorphous Indium‐Gallium‐Zinc Oxide by Capping a Strong Reduction Layer , 2012, Advanced materials.

[41]  Mallory Mativenga,et al.  Amorphous-InGaZnO4 Thin-Film Transistors with Damage-Free Back Channel Wet-Etch Process , 2012 .

[42]  Jae Kyeong Jeong,et al.  Improvement in both mobility and bias stability of ZnSnO transistors by inserting ultra-thin InSnO layer at the gate insulator/channel interface , 2011 .

[43]  Wei Wang,et al.  Novel planar-structure electrochemical devices for highly flexible semitransparent power generation/storage sources. , 2013, Nano letters.

[44]  Hong-Gyu Kim,et al.  Oxide TFT with multilayer gate insulator for backplane of AMOLED device , 2008 .

[45]  P. Lai,et al.  Fluorinated InGaZnO Thin-Film Transistor With HfLaO Gate Dielectric , 2014, IEEE Electron Device Letters.

[46]  A. Facchetti,et al.  High-performance transparent inorganic–organic hybrid thin-film n-type transistors , 2006, Nature materials.