Hot-carrier reliability study of second and first impact ionization degradation in 0.15-μm channel-length N-MOSFETS

✍ Scribed by A. Bravaix; D. Goguenheim; N. Revil; E. Vincent

• Book ID: 104305667
• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 232 KB
• Volume: 59
• Category: Article
• ISSN: 0167-9317
• DOI: 10.1016/s0167-9317(01)00679-7

✦ Synopsis

The hot-carrier degradation induced by first-and second-impact ionization events is compared in advanced N-MOSFETs used for digital applications with a 3.2-nm gate-oxide thickness. Results show that the substrate enhanced electron injection (SEEI) mechanism is still increased in 0.15-mm channel length devices with p-pockets and shallow drain junctions with a measured much higher injection efficiency than that in older technologies. The enhancement of the gate current originates from tunneling contributions and from the secondary-primary-hot electron currents at low energy. The induced damage is explained solely by the interface trap generation and mobility reduction in 3.2-nm thick gate-oxide devices. The difference between first and second hot-carrier damage is related to the extension of the degraded region toward the source. This is in contrast to thicker gate-oxide N-devices where the SEEI effect is weak and where the electron trapping extends from the gate-drain overlap region toward the source in addition to the generated interface traps.