Ferroelectric Dielectrics Integrated on Silicon

Chapter 9Reliability of PZT Capacitors ¹

 

 

 

9.1. Introduction

The new generation of mobile phones includes hundreds of discrete components such as resistors, inductors, capacitors, and diodes, which provide functions such as signal treatment and protection. When they are classically encapsulated into individual packages, these components occupy a significant space inside the board circuits. To deal with this issue, the trend suggested by the suppliers of discrete components is now to incorporate a maximum number of devices, active and passive, within a single chip. These new products thus contribute to the clutter’s reduction. However, the integration of discrete components within a single system remains a high-level technological challenge, which requires the development of new technologies combining protection diodes, resistors, and high-density capacitors. The development of new capacitor generations can be considered as the main technological obstacle for the development of these products. The imposed capacitive densities, of the order of several tens of nanoFarad per square millimeter, involve the use of high-dielectric permittivity materials, called “high-K” materials. Ferroelectric materials like PZT are good candidates for the development of these capacitors, but these materials are not well known in the world of microelectronics, particularly in terms of reliability performances.

By definition, the reliability of an element or a set of element is the probability that ...