AVS 47th International Symposium
    Plasma Science and Technology Wednesday Sessions
       Session PS+MS-WeM

Paper PS+MS-WeM6
Aspect Ratio Dependent Plasma-Induced Charging Damage in RF Pre-Cleaning of Metal Contact

Wednesday, October 4, 2000, 10:00 am, Room 311

Session: Plasma-Induced Damage
Presenter: J. Kim, Samsung Electronics, Korea
Authors: J. Kim, Samsung Electronics, Korea
K.S. Shin, Samsung Electronics, Korea
W.J. Park, Samsung Electronics, Korea
C.J. Kang, Samsung Electronics, Korea
T.-H. Ahn, Samsung Electronics, Korea
J.-T. Moon, Samsung Electronics, Korea
Correspondent: Click to Email
As the packing density increases in the fabrication of semiconductor, the aspect ratio and the CD (Critical Dimension) of a metal contact are exponentially aggravated in the dry etch process. The aspect ratio dependency on a plasma-induced charging damage during the RF pre-cleaning of a metal contact has been evaluated with the two dimensional Monte-Carlo simulation and the related experiments. From the simulation of a metal contact opened on a gate metal, it is found that the potential on a metal contact bottom, which is directly related to plasma-induced charging damage, is saturated near 4 of aspect ratio after linearly increasing with the aspect ratio. However, the linear decrease of CD of a metal contact exponentially increases the potential stress on gate oxide. These simulation results are confirmed with the two different experiments, an in-situ charge-up monitoring and the electric test of a fully fabricated CMOS wafers. A phase-controlled inductively coupled plasma is proposed to suppress the plasma-induced charging damage. With the phase-controlled inductively coupled plasma, the plasma-induced damage is strongly suppressed when the phase delay of the bias power to the source power is near 180 degree.