Suppression of temperature instability in InGaZnO thin-film transistors by in situ nitrogen doping

Abstract

We have investigated the effect of nitrogen doping on the behavior of hysteresis curve and its suppression of temperature instability in amorphous InGaZnO thin-film transistors (a-IGZO TFTs). The in situ nitrogen doping reduced the temperature induced abnormal sub threshold leakage current and traps generation. Large falling-rate (F R ) ∼ 0.26 eV V −1 , low activation energy (E a ) ∼ 0.617 eV and a small hysteresis compared to the pure a-IGZO TFTs, shows the best immunity to thermal instability. This is mainly attributed to the reduction of interface trap density and oxygen vacancies due to the passivation of defects and/dangling bonds.

Polymer Solar Cells with Efficiency >10% Enabled via a Facile Solution‐Processed Al‐Doped ZnO Electron Transporting Layer

“…[ 47 ] More recently, Zhao et al [ 48 ] and Chen et al [ 49 ] reported on highly-effi cient fl exible inverted polymer solar cells, achieving PCEs >8% with PFN as the ETL and by exploiting microcavity and plasmonic effects, respectively. [ 7,18,21,22,37 ] Our protocol includes an ammonia-treatment of the aqueous AZO nanoparticle solution (s-AZO) to produce more compact, crystalline, and smooth buffer layers that retain Al doping while incorporating N in small amounts (<1 at%), [52][53][54] leading to improved passivation of the dangling bonds. [ 50 ] In this contribution, we report on the facile and lowtemperature (125 °C) solution-processed deposition of AZO buffer layers-an effective approach in the making of electron transporting/hole blocking buffer layers for a wide range of polymer:PCBM BHJ systems-and demonstrate maximum PCEs of over 10% on glass and over 8% on plastic substrates without the requirement for ETL surface modifi cation/passivation.…”

Amorphous Oxide Thin Film Transistors with Nitrogen-Doped Hetero-Structure Channel Layers

“…We reported that larger concentration variation of V O in AOS TFTs could lead to serious V TH shift during the thermal testing [29]. In addition, the literature [16,34] indicated that N-doping suppressed V O formation in the bulk channels for the thermal tests of a-IGZO:N TFTs. Hence, the better thermal stability of Sample II might be attributed to the a-IGZO:N films, which acted as a passivation layer and suppressed the V O formation in the a-IZO:N layers.…”

Understanding hydrogen and nitrogen doping on active defects in amorphous In-Ga-Zn-O thin film transistors

“…Interstitial hydrogen (H i ) is also predicted to act exclusively as a donor, i.e., always in the 1þ charge state. 27 These induced Ho and H i defects are denoted by the purple bar and dashed curve in Fig. 1(b) and related to the large negative shift of V TH and V 0 observed in the a-IGZO TFT with "H:100 s." N is often considered as a promising p-type dopant and to serve as defect binder (i.e., facile substitution) due to its ionic radius close to that of O defects related to Vo.…”

“…These observations imply that traps can be neutralized by a proper amount of H/N co-doping. It is indeed well known that the V TH and SS of the TFTs are related to the interface trap density (D it ) and the number of deep states, such that SS can be described as 27…”