Semiconductor Device Reliability
[As of Jan, 2010]
Following the introduction of 3.0-micron devices (64K DRAMs) in 1975, 2.0-micron devices (256K DRAMs) in 1980 and 1.2-micron devices (1M DRAMs) in 1985, we have now entered the age of submicron devices (4M, 16M and 256M DRAMs). A 45nm DRAM is now under development and scheduled for mass production around the year 2008, making built-in quality and reliability increasingly critical.
To meet such needs of today, Toshiba has established target quality and reliability levels for the following:
- Reliability verification of newly developed processes and design rules
- Reliability verification of new packages
- Reliability verification of products
This is done at each step of the qualification process, from the product development phase to set the quality and reliability gate (QGate).
In addition, the reliability levels of mass produced products are monitored periodically so as to verify that the established reliability levels have been met. Failures during these evaluation processes are analyzed and the failure mechanism for each failure is clearly defined, making every effort to improve the manufacturing process.
This chapter describes the concept of reliability, the factors that affect reliability, and failure mechanisms.