Abstract
Transparent bottom-gate amorphous Indium-Gallium-Zinc Oxide (a-IGZO) thin-film transistors (TFTs) had been successfully fabricated at relative low temperature. The influence of reaction gas ratio of N2O and SiH4 during the growth of etching stop layer (SiOx) on the characteristics of a-IGZO TFTs was investigated. The transfer characteristics of the TFTs were changed markedly because active layer of a-IGZO films was modified by plasma in the growth process of SiOx. By optimizing the deposition parameters of etching stop layer process, a-IGZO TFTs were manufactured and exhibited good performance with a field-effect mobility of 8.5 cm2V-1s-1, a threshold voltage of 1.3 V, and good stability under gate bias stress of 20 V for 10000 s.
Highlights
A-IGZO thin-film transistors (TFTs) backplanes for active-matrix liquid crystal display (AMLCD) or activematrix organic light-emitting diode display (AMOLED) displays widely adopt the bottom gate structure with etching stop layer or passivation layer[6] in order to overcome the IGZO damage induced by the process of source/drain (SD) electrodes sputtering and wet etching selectivity of IGZO/SD electrodes due to amorphous In-Ga-Zn-O (a-IGZO) with a fast rate of dissolution in wet etching process using acid
We investigated the effect of the etching stopper layer (SiOx) on the characteristics of a-IGZO TFTs
In order to reveal the mechanism of the effect of growth process of etching stop layer on characteristics of TFT devices, the electrical properties of a-IGZO films were studied
Summary
Amorphous oxide semiconductors (AOSs) are emerging as promising materials for active layers of thin-film transistors (TFTs) applied in active-matrix liquid crystal display (AMLCD) and activematrix organic light-emitting diode display (AMOLED) backplanes.[1,2] Among those AOSs, an amorphous In-Ga-Zn-O (a-IGZO) has attracted much attention due to advantages of a high field effect mobility, excellent uniformity, and the compatibility with transparent and flexible substrate, as compared to conventional amorphous and polycrystalline silicon.[3,4,5] Generally, a-IGZO TFT backplanes for AMLCD or AMOLED displays widely adopt the bottom gate structure with etching stop layer or passivation layer[6] in order to overcome the IGZO damage induced by the process of source/drain (SD) electrodes sputtering and wet etching selectivity of IGZO/SD electrodes due to a-IGZO with a fast rate of dissolution in wet etching process using acid. Plasma process plays an important role on the electrical property of IGZO-TFT during the process of etching stop layer or passivation layer grown using PECVD.[7] the origin is not clear yet. It is crucial to investigate the effect of the etching stopper layer on the characteristics of a-IGZO TFTs because of the plasma-induced change during etching stopper layer process. We investigated the effect of the etching stopper layer (SiOx) on the characteristics of a-IGZO TFTs. The characteristics of the TFTs were found to be highly dependent on the deposition conditions of these etching stopper layers. By optimizing process parameters of etching stopper layers, the threshold voltage (Vth) of the TFTs can be well controlled to the desired range
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.