Ferroelectric properties of Pt∕PbTiO3∕PbZr0.3Ti0.7O3∕PbTiO3∕Pt integrated capacitors etched in noncrystalline phase

Abstract

Uniformly patterned Pt∕PbTiO3∕PbZr0.3Ti0.7O3∕PbTiO3∕Pt capacitor arrays were etched in noncrystalline phase. The ferroelectric layer was well crystallized and contains uniform grains. The capacitors exhibit well-saturated hysteresis loop and excellent fatigue properties in terms of larger saturation polarization Pmax of 53.2μC∕cm2 at an applied voltage of 12V, higher remnant polarization Pr of 30.5μC∕cm2 for a coercive field of 58kV∕cm, remnant polarization of about 81.2% at 1010 switching cycles, and a low leakage current density of 10−8A∕cm2 at an applied voltage of 3V. The etching effects on the properties of capacitor were reduced to minimal values, confirmed by scanning electron microscope, energy-dispersive x-ray microanalysis, and piezoresponse force microscopy results. The reliable electric properties and fine profile of the patterns indicate that the capacitors are suitable for ferroelectric random access memories and other integrated ferroelectric devices.

Nanoscale and Spatial Variations Investigation of Etch Damage in Integrated Ferroelectric Capacitor Side Wall by Piezoresponse Force Microscopy

“…The details of the typical integrated process and the innovated integrated process were given elsewhere. 1,2,10) The sandwich structure ferroelectric thin films PbTiO 3 /PbZr 0:3 Ti 0:7 O 3 /PbTiO 3 (PT/ PZT/PT) were deposited by sol-gel method. 11) The ferroelectric capacitors fabricated by the typical integrated process and the innovated integrated process are denoted by ''TIP-FeCAP'' and ''IIP-FeCAP'', respectively.…”

“…Up to now, dry etching has become one of the critical processes for the pattern transfer in Si integrated circuit devices. 1,2) The ferroelectric films are very sensitive to high density plasma occurring during dry etching process, and giving rise to the degradation of the electrical properties because of physical damage and chemical residue contamination in the etchingdamaged surface layers and side wall of ferroelectric capacitors. [3][4][5][6] Therefore, the investigating etching damage and the understanding degradation of electric properties in ferroelectric thin films are very important.…”

Nanoscale investigation of side wall and surface domain structures in multilayer PbTiO3/PbZr0.3Ti0.7O3/PbTiO3thin films

“…The Pt/PT/PZT/PT/Pt capacitors were integrated by an innovative process. Details of the processing and properties of the capacitor are given elsewhere [8,9,14].…”

“…We recently reported an innovative ferroelectric capacitor integrated process [8,9]. The investigation of the properties of the Pt/PbTiO 3 /PbZr 0.3 Ti 0.7 O 3 /PbTiO 3 /Pt (Pt/PT/PZT/PT/Pt) capacitor indicated that the etch damage was minimized by the innovative process.…”

Characterization and reliability studies towards piezoelectrically actuated RF-MEMS switches

“…It has been reported that PZT properties are influenced by fabrication processing, especially plasma etching [135][136][137][138][139][140][141][142][143][144]. Nowadays, with the decreasing of device feature size, plasma etching (or dry etching) is more widely used than wet etching, because of its an-isotropic and accurate pattern transfer for PZT [145]. The further development of RF-MEMS switches application requires an increased integration density.…”