AVS 52nd International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS-TuA

Paper PS-TuA5
Modeling of Organic Low-k Etching in a Two Frequency Capacitively Coupled Plasma in N@sub 2@/H@sub 2@

Tuesday, November 1, 2005, 3:20 pm, Room 302

Session: Dielectric Etch II
Presenter: K. Ishihara, Keio University, Japan
Authors: K. Ishihara, Keio University, Japan
C. Shon, Keio University, Japan
T. Yagisawa, Keio University, Japan
T. Shimada, Keio University, Japan
T. Makabe, Keio University, Japan
Correspondent: Click to Email
The dimension of ULSI device elements continues to shrink in size and multi-layer interconnect system with Low-k materials is employed to reduce RC signal delay in interconnect. We have two main groups of Low-k materials, i.e., organic and inorganic. Low-k materials have distinct characteristics, such as poor mechanical strength and low heat transfer. Under these circumstances, low tempareture plasma source with low damage is practically needed for Low-k material etching. Capacitively coupled N@sub 2@/H@sub 2@ plasma in parallel plate geometry is considered to be the source for organic Low-k material etching. N and H radicals produced in the collision dominated plasma will play important roles on the characteristics of the etching. In our previous work, we have investigated plasma characteristics in N@sub 2@(50%)/H@sub 2@ in two frequency capacitively coupled plasma (2f-CCP) reactor by using VicAddress. In the present study, we have developed the radical transport to the wafer in 2f-CCP by considering the production paths in both gas and surface phases, and obtained the velocity distribution of ions, H@super +@, H@sub 2@@super +@, H@sub 3@@super +@, and N@sub 2@@super +@ incident on the wafer surface. The radical density agrees well with the experimental. Feature profile evolution in a patterned organic Low-k material will be demonstrated in the 2f-CCP reactor in N@sub 2@(50%)/H@sub 2@.