AVS 53rd International Symposium
    Plasma Science and Technology Thursday Sessions
       Session PS-ThP

Paper PS-ThP4
Spectroscopic Study of Fluorocarbon Plasma Gas Phase Chemistries in High Density Plasma for a Submicron Contact Hole Etching

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: High Pressure Discharges and Novel Diagnostics & Sources Poster Session
Presenter: G.H. Kim, ETRI, Korea
Authors: G.H. Kim, ETRI, Korea
K.T. Kim, Chung-Ang University, Korea
C.I. Kim, Chung-Ang University, Korea
S.G. Kim, ETRI, Korea
J.G. Koo, ETRI
T.M. Roh, ETRI, Korea
J.D. Kim, ETRI, Korea
Correspondent: Click to Email
As ultra large scale integrated (ULSI) devices are scaled down, highly selective SiO@sub 2@ etching and submicron contact hole etching process are increasingly required. Silicon nitride is used as a passivation layer that protects circuits from mechanical and chemical attack, or as an etch stop layer, enabling the fabrication of certain damascene and self-aligned contact (SAC) structures. Previous studies focused on either anisotropic etching or selective etching of SiO@sub 2@ over Si@sub 3@N@sub 4@ or Si using conventional low density plasma sources. Recently, high density plasma (HDP) single wafer etching tools have attracted a lot of attention, mainly because HDP sources operate at low pressure and allow independent control of ion flux and ion energy. Consequently, the plasma-surface interactions become significant, and surface conditions such as the temperature and cleanliness of the reactor wall play an important role determining both the gas phase chemistries and the surface reactions deposition and etching on the wafer surface. In this study, we present a highly selective SiO@sub 2@ etching and submicron contact hole etching with a hydro-fluorocarbon gas (CHF@sub 3@ and CH@sub 2@F@sub 2@) in addition to CF@sub 4@ and C@sub 4@F@sub 8@ plasma chemistry in high density plasma and discuss the important species required for protecting the nitride surface and controlling the polymer inhibitor by using optical emission spectroscopy and X-ray photoelectron spectroscopy.