Photo Misalignment Impact on the Hot Carrier Reliability of Lateral DMOS Devices

Power management devices often require operation in the 20 V to 30 V range. A common choice for the power MOS driver is an n-channel lateral DMOS (N-LDMOS) device. An advantage of N-LDMOS device is that it can easily be integrated within existing technologies to handle a wide range of operating voltages without significant process changes. Because of the high voltages applied to the N-LDMOS device hot carrier (HC) degradation is a real reliability concern. In high power applications N-LDMOS devices are often implemented in transistor arrays where the basic cell is a dual gate single drain device. This paper focuses on understanding unusual N-LDMOS HC results in which single gate devices had significantly better HC performance than dual gate devices.