Comparative study of source-drain contact metals for amorphous InGaZnO thin-film transistors

作者：Nag Manoj^*; Bhoolokam Ajay; Steudel Soeren; Chasin Adrian; Groeseneken Guido; Heremans Paul

来源：Journal of the Society for Information Display, 2014, 22(6): 310-315.

DOI：10.1002/jsid.250

• amorphous oxide semiconductors
• contact metal
• a-IGZO
• TFTs
• bias-stress stability

In this work, we compared the thin-film transistor (TFT) characteristics of amorphous InGaZnO TFTs with six different source-drain (S/D) metals (MoCr, TiW, Ni, Mo, Al, and Ti/Au) fabricated in bottom-gate bottom-contact (BGBC) and bottom-gate top-contact (BGTC) configurations. In the BGTC configuration, nearly every metal can be injected nicely into the a-IGZO leading to nice TFT characteristics; however, in the BGBC configuration, only Ti/Au is injected nicely and shows comparable TFT characteristics. We attribute this to the metal-containing deposits in the channel and the contact oxidation during a-IGZO layer sputtering in the presence of S/D metal. In bias-stress stability, TFTs with Ti/Au S/D metal showed good results in both configurations; however, in the BGTC configuration, not all the TFTs showed as good bias results as Ti/Au S/D metal TFTs. We attribute this to backchannel interface change, which happened because of the metal-containing deposits at the backchannel during the final the SiO2 passivation.

• 出版日期2014-6