Effects of residual stresses on lead–zirconate–titanate (PZT) thin-film membrane microactuators

2010 ◽  
Vol 159 (1) ◽  
pp. 88-95 ◽  
Author(s):  
Cheng-Chun Lee ◽  
G.Z. Cao ◽  
I.Y. Shen
Keyword(s):  
Thin Film ◽  
Residual Stresses ◽  
Lead Zirconate Titanate ◽  
Lead Zirconate ◽  
Zirconate Titanate ◽  
Pzt Thin Film ◽  
Thin Film Membrane

Correlations Among Degradations in Lead Zirconate Titanate thin Film Capacitors

1993 ◽  
Vol 310 ◽  
Author(s):  
In K. Yoo ◽  
Seshu B. Desu ◽  
Jimmy Xing
Keyword(s):  
Thin Film ◽  
Leakage Current ◽  
Lead Zirconate Titanate ◽  
Oxygen Vacancies ◽  
Lead Zirconate ◽  
Electrical Degradation ◽  
Zirconate Titanate ◽  
Thin Film Capacitors ◽  
Pzt Thin Film ◽  
Degradation Properties

AbstractMany attempts have been made to reduce degradation properties of Lead Zirconate Titanate (PZT) thin film capacitors. Although each degradation property has been studied extensively for the sake of material improvement, it is desired that they be understood in a unified manner in order to reduce degradation properties simultaneously. This can be achieved if a common source(s) of degradations is identified and controlled. In the past it was noticed that oxygen vacancies play a key role in fatigue, leakage current, and electrical degradation/breakdown of PZT films. It is now known that space charges (oxygen vacancies, mainly) affect ageing, too. Therefore, a quantitative ageing mechanism is proposed based on oxygen vacancy migration under internal field generated by either remanent polarization or spontaneous polarization. Fatigue, leakage current, electrical degradation, and polarization reversal mechanisms are correlated with the ageing mechanism in order to establish guidelines for simultaneous degradation control of PZT thin film capacitors. In addition, the current pitfalls in the ferroelectric test circuit is discussed, which may cause false retention, imprint, and ageing.

Effects of Added Mass on Lead-Zirconate-Titanate (PZT) Thin-Film Microactuators in Aqueous Environments

2013 ◽  
Author(s):  
Chuan Luo ◽  
Chen-Wei Yang ◽  
G. Z. Cao ◽  
I. Y. Shen
Keyword(s):  
Thin Film ◽  
Lead Zirconate Titanate ◽  
Silicon Substrate ◽  
Laser Doppler Vibrometer ◽  
Lead Zirconate ◽  
Added Mass ◽  
Surrounding Water ◽  
Zirconate Titanate ◽  
Pzt Thin Film ◽  
Aqueous Environments

In this paper, we conduct experimental and theoretical studies of a lead-zirconate-titanate (PZT) thin-film microactuator probe submerged in water. The microactuator consists of a base silicon diaphragm, a layer of bottom electrode, a layer of lead-zirconate-titanate (PZT) thin film, and a layer of top electrode. The diaphragm is anchored on a silicon substrate by etching the silicon substrate from the back to form a cavity under the diaphragm. The diaphragm along with part of its anchor is then diced off from the silicon substrate to form a PZT probe and subsequently packaged with parylene. The probe tip has dimensions of 1 mm × 1 mm × 0.4 mm, while the diaphragm has dimensions of 800 μm × 800 μm × 2 μm. In the experimental study, frequency response functions of actuator displacement are measured via a laser Doppler vibrometer and a spectrum analyzer. The measurements show that the first natural frequency of the microactuator reduces from 80 kHz in air to 20 kHz when the microactuator is submerged in water. A literature search indicates that the surrounding water induces significant added mass to the microactuator. Estimation of the added mass based on theories in fluid mechanics successfully reconcile the predicted frequency to the vicinity of 20 kHz confirming the effects of added mass.

The Role of the Lead Zirconate Titanate (PZT)-Pt Interface in the Anomalous Phase Transformation Kinetics in Sputtered Pzt Thin Film Capacitors at Sub-2000 Å Thicknesses

1991 ◽  
Vol 243 ◽  
Author(s):  
Vinay Chikarmane ◽  
Jiyoung Kim ◽  
C. Sudhama ◽  
Jack Lee ◽  
Al Tasch ◽  
...  
Keyword(s):  
Thin Film ◽  
Phase Transformation ◽  
Lead Zirconate Titanate ◽  
Lead Zirconate ◽  
Initial Increase ◽  
Transformation Kinetics ◽  
Pzt Film ◽  
Zirconate Titanate ◽  
Phase Transformation Kinetics ◽  
Pzt Thin Film

AbstractThe Pt-Lead Zirconate Titanate (PZT) thin film interface plays a key role in determining the electrical properties and phase transformation kinetics of Pt-PZT-Pt thin film capacitor structures. The results of the electrical and material properties of PZT (65/35) films that vary in thickness between 500 Å to 4000 Å deposited by DC-magnetron sputtering under identical deposition conditions, and subjected to the same post-deposition thermal processing conditions shows that the Pt-PZT interface dominates thin film properties at low thicknesses (≦ 2000 Å). The charge storage density (Qc') and maximum polarization (Pmax) shows an anomalous variation with thickness, showing an initial increase followed by a drastic decrease as the film thickness is scaled down to 500Å. Significant interdiffusion at the PZT film-Pt electrode retards the pyrochlore-to-perovskite phase transformation nucleation and growth rate in PZT films of thickness 2000Å and lower. Gate polarity dependence of the time-tobreakdown and the degradation field is observed for all PZT film thicknesses (including 4000Å). This indicates that the ferroelectric film-electrode interface has an important role to play in determining the electrical reliability properties even in the 4000Å thick PZT film, although Qc' and Pmax are not adversely affected at these thicknesses.

Sign in / Sign up

Export Citation Format

Share Document