IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Dielectrics Monday Sessions
       Session DI2-MoP

Paper DI2-MoP5
Etching Characteristics of Polyimide Film as Interlayer Dielectric Using Inductively Coupled Plasma

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: Low K Dielectrics Poster Session
Presenter: P.S. Kang, Chung-Ang University, Korea
Authors: P.S. Kang, Chung-Ang University, Korea
C.I. Kim, Chung-Ang University, Korea
S.G. Kim, ETRI, Korea
H.S. Choi, Juseong College, Korea
C.I. Lee, Ansan College of Technology, Korea
E.G. Chang, Chung-Ang University, Korea
Correspondent: Click to Email
In ultra-large-scale integrated circuits, where critical dimensions continue to shrink into the deep submicrometer range, RC constant becomes an increasingly dominant factor in governing both the velocities of operation and the corresponding power consumption. One method to reduce RC constant is the reduction of the dielectric constant of the intermetal material. Therefore, many low-k materials such as amorphous carbon, Teflon, SiOF, Polyimide have been studied by the various research institutes. Among them polyimide (PI) films are widely due to low dielectric constant ,low water absorption, high gap-fill and planarization capability. In this study, etching characteristics of polyimide film with O@sub 2@/CF@sub 4@ gas mixing was studied using inductively coupled plasma (ICP). The etch rate and selectivity were evaluated to rf power, dc-bias voltage, chamber pressure, and substrate temperature. High etch rate (over 10000Å/min) and vertical profile was acquired in CF@sub 4@/(CF@sub 4@+O@sub 2@) of 0.2. The selectivities of polyimide to PR and SiO@sub 2@ was 1.1, 34, respectively. The profiles of polyimide film etched in CF@sub 4@/O@sub 2@ were measured by a scanning electron microscope (SEM) with using an aluminum hard mask pattern. The chemical states on the PI film surface were measured by x-ray photoelectron spectroscopy (XPS). Ion current density and plasma density of O radical and fluorine in O@sub 2@/CF@sub 4@ were investigated by Langmuir probe and optical emission spectrometer (OES). After the etching process, leakage current and dielectric constant were characterized by semiconductor parameter analyzer (HP4145B) and impedance analyzer (HP 4192 at 1MHz) using Al/PI/Al capacitor.