Techniques for structuring Lead-Lanthanum-Zirconium-Titanium

Abstract

This thesis describes different approaches for etching of Lead Lanthanum Zirconate Titanate, PLZT, and Lead Zirconate Titanate, PZT. PZT and PLZT are ceramic ferroelectric materials. They are used in applications ranging from FRAM to electro-optical devices and photonic crystal waveguides. This thesis presents the basic theory of ferroelectricity and piezoelectricity. The main ferroelectric and electro-optic properties of PLZT and PZT is then described. The background theory of pattering techniqes is presenteted. The main focus of this thesis, is on describing and comparing previous published work on PLZT and PZT etch characteristics. The findings are summarized and recommendation for suitable etch parameters given. Good etch results can be achieved in both fluorine and chlorine plasmas. Common is a chamber pressure of about 5mTorr and that the etch rate increases linearly with radical concentration and sputtering energy.