AVS 47th International Symposium
    Plasma Science and Technology Wednesday Sessions
       Session PS-WeP

Paper PS-WeP20
Numerical Study of HBr/O@sub 2@/CF@sub 4@ and HBr/O@sub 2@/CHF@sub 3@ Etching Chemistry in an Inductively Coupled Plasma Reactor

Wednesday, October 4, 2000, 11:00 am, Room Exhibit Hall C & D

Session: Poster Session
Presenter: X. Xu, LSI Logic Corporation
Authors: X. Xu, LSI Logic Corporation
P. Schoenborn, LSI Logic Corporation
Correspondent: Click to Email
Inductively coupled plasmas (ICPs) have been developed for various applications in the modern integrated circuit manufacturing industry. One important ICP applicator for device fabrication is plasma etching of Si and other microelectronics materials because ICP reactors can produce high plasma density (10@super 11@ - 10@super 12@ cm@super -3@) at low pressure (a few to 10s mTorr). Increasingly stringent control of etching rates, profile shapes, and uniformity has led to using more complex chemistry mixtures in the selective etching of submicron features. There has been increasing interest in mixtures of HBr and fluorocarbons for etching of polysilicon and Si@sub 3@N@sub 4@ due to improved selectivity and superior control of the etched side wall profile. An understanding of the plasma chemistry is necessary and useful to examine plasma behavior from the source region to the substrate such as the fluxes of radicals and ions. In this study, we investigate the scaling of plasma chemistry mechanism of HBr/O@sub 2@/CF@sub 4@ and HBr/O@sub 2@/CHF@sub 3@ in an inductively coupled plasma reactor through a plasma simulation tool, the Hybrid Plasma Equipment Model (HPEM) developed at the University of Illinois. Addition of HBr into fluorocarbon plasmas cause significant reduction in F density. Results show that increasing gas pressure results in an enhanced Br flux and a diminished F flux in to the wafer. We will discuss the consequences of etching results of Si@sub 3@N@sub 4@.