Aging effects on the stability of nitrogen-doped and un-doped InGaZnO thin-film transistors. (September 2015)

• Record Type: Journal Article
• Authors: Raja, Jayapal; Jang, Kyungsoo; Balaji, Nagarajan; Qamar Hussain, Shahzada; Velumani, S.; Chatterjee, Somenath; Kim, Taeyong; Yi, Junsin
• Is Part Of: Materials science in semiconductor processing. Volume 37(2015:Sep.)
• Page Start: 129
• Page End: 134
• Publication Date: 2015-09
• Subjects: Oxygen desorption -- Shelf-life stability -- InGaZnO -- Moisture adsorption; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2015.02.036
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: The long-term electrical reliability/stability measurements, including negative bias stress and aging over 10 months of nitrogen-doped (N-doped) and un-doped amorphous InGaZnO thin-film transistors (a-IGZO TFTs) were investigated. Aged un-doped a-IGZO TFT exhibits larger threshold voltage shift (Δ V th ) of 2.43 V and turn on voltage shift (Δ V on ) of 5.37 V due to combination of the surface desorption of oxygen atoms and moisture adsorption. The noticeable decrease in Δ V th (0.93 V) and Δ V on (0.81 V) of in-situ nitrogen doped a-IGZO TFT indicates the surface interaction is prevented due to effective passivation of inactive oxygen׳s in the channel. After 10 months aging time, the Δ V th (~2.66 V) and Δ V on (~4.62 V) of un-doped devices were observed under the negative gate bias stress, which is comparable to ~0.83 V and ~0.85 V in nitrogen doped a-IGZO devices, respectively. The perspectives reported here shall be useful in fabricating passivation-free oxide based semiconductor TFTs for device operation in stable ambient conditions.