AVS 49th International Symposium
    Plasma Science Wednesday Sessions
       Session PS+TF-WeP

Paper PS+TF-WeP16
Effects of Substrate Temperature on the Etching of Silver Films using Inductively Coupled Halogen-based Plasmas

Wednesday, November 6, 2002, 11:00 am, Room Exhibit Hall B2

Session: Plasma Etching & Deposition
Presenter: S.D Park, Sungkyunkwan University, Korea
Authors: S.D Park, Sungkyunkwan University, Korea
Y.J. Lee, Sungkyunkwan University, Korea
S.G. Kim, Samsung Electronics, Korea
H.H. Choe, Samsung Electronics, Korea
M.P. Hong, Samsung Electronics, Korea
G.Y. Yeom, Sungkyunkwan University, Korea
Correspondent: Click to Email
Silver(Ag) is one of the potential materials in thin film transistor liquid crystal display (TFT-LCD) because of its lowest bulk resistivity of all metals at room temperature and high reflectivity. Also, it is one of the attractive candidates for the intergrated circuit(IC) manufacturing. Currently, Ag etching is performed using wet etching methods, however, for the fabrication of the high resolution display devices, the use of plasma etching process is indispensable. In reality, there are several problems to be solved before Ag plasma etching to be applied to TFT-LCD processing. The main problems are the formation of involatile etch products, low etch rates, and high surface roughness after removing the etch products. For example, many works on Ag etching using halogen-based plasma have been studied, however, slow etch rates lower than 100nm/min and a thick involatile Ag etch products remaining during the etching were reported. Therefore, in this study, using an inductively coupled halogen-based plasma, the effects of substrate temperature were investigated to obtain higher Ag etch rates without remaining any involatile etch products. The results showed that when the substrate temperature was increased above 70°, the etch rate higher than 250nm/min could be obtained and, when Ar is added to halogen plasma, Ag etch products were effectively removed during the etching because of the increase of sputtering effect of etch products. To understand have the Ag etching characteristics, the optical emission spectroscopy(OES) and X-ray photoelectron spectroscopy(XPS) have been used and measured as a function of gas combination and substrate temperature. Also, a scanning electron microscope(SEM) was used to observed as-etched Ag surfaces.