Hot Carrier Degradation of Sub-micron N-channel MOSFETs Subject to Static Stress
Author | : Payman G. Aminzadeh |
Publisher | : |
Total Pages | : 112 |
Release | : 1993 |
ISBN-10 | : OCLC:36035177 |
ISBN-13 | : |
Rating | : 4/5 (77 Downloads) |
Download or read book Hot Carrier Degradation of Sub-micron N-channel MOSFETs Subject to Static Stress written by Payman G. Aminzadeh and published by . This book was released on 1993 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hot carrier effects in sub-micron lightly doped drain (LDD) n-channel MOSFETs under static (DC) stress are studied in order to establish the degradation mechanisms of such devices. Degradation is monitored as a function of time at various gate voltages. Under accelerated aging conditions (i.e. large drain voltages) the gate voltage for maximum degradation is found to be different than the gate voltage for which the substrate current is maximum; this is in contrast to the results of previous workers who found degradation and substrate current to be strongly correlated. However, under normal operating conditions, degradation and substrate current are found to be correlated. Furthermore, through the use of charge pumping measurements it is shown that two primary mechanisms are accountable for the degradation of these devices at small and large gate voltages. First, at large gate voltages there is an increase in the degradation which is predominantly due to electron injection and trapping in the oxide. An alternating static injection experiment shows that this type of electron trapping degradation is recoverable. Second, at small gate voltages degradation is mainly related to interface state generation near the drain LDD region. Floating gate measurements demonstrate that electron and hole injection occurs at large and small gate voltages, respectively. It is also shown that maximum interface state creation occurs when electron and hole injection happens simultaneously.