FinFET Drain Region Dopant Gradient Reduces Hot Carrier Injection

The patent applies local quality by creating different dopant concentration zones within the drain region. Specifically, the drain extension region has a first dopant concentration while the main drain region has a second, lower dopant concentration. This local differentiation allows the drain extension to provide good conductivity and carrier injection while the main drain region maintains lower HCI, thus resolving the contradiction between overall device performance and local HCI reduction.

The patent changes the dopant concentration parameter spatially within the device structure. By implementing a gradient or stepped dopant profile where the drain extension has higher concentration (first dopant concentration) and the main drain has lower concentration (second dopant concentration), the patent optimizes both conductivity and HCI reduction. This parameter variation resolves the contradiction by allowing high performance where needed while minimizing harmful effects in critical regions.

The patent applies local quality by differentiating the dopant concentration between the drain extension and main drain regions. The drain extension region with higher dopant concentration facilitates carrier injection and maintains good conductivity, while the main drain region with lower dopant concentration reduces hot carrier generation even at high breakdown voltages. This local differentiation allows the device to achieve high voltage capability while minimizing hot carrier effects.

The patent segments the drain region into two distinct zones: the drain extension region and the main drain region. Each zone has optimized dopant concentration for its specific function. The drain extension handles carrier injection with higher doping, while the main drain handles high voltage with lower doping to reduce hot carrier generation. This segmentation resolves the contradiction between breakdown voltage and hot carrier generation.