System and method for mitigating oxide growth in a gate dielectric

摘要

Oxide growth of a gate dielectric layer that occurs between processes used in the fabrication of a gate dielectric structure can be reduced. The reduction in oxide growth can be achieved by maintaining the gate dielectric layer in an ambient effective to mitigate oxide growth of the gate dielectric layer between at least two sequential process steps used in the fabrication the gate dielectric structure. Maintaining the gate dielectric layer in an ambient effective to mitigate oxide growth also improves the uniformity of nitrogen implanted in the gate dielectric.

主权项

1. A transistor device having a gate dielectric, a gate electrode, a source region and a drain region, wherein the gate dielectric is formed by a process comprising the steps of:
forming a dielectric layer on a substrate in a first process chamber of a processing system, the first process chamber having a first pumping element configured to evacuate gas from the first process chamber; introducing nitrogen atoms in the dielectric layer using a plasma process in a second process chamber of the processing system, the second process chamber having a second pumping element configured to evacuate gas from the second process chamber; performing a thermal process in a third process chamber; transferring the substrate between the first process chamber, the second process chamber, and the third process chamber through a transfer chamber of the processing system, wherein the transfer chamber is connected to the first process chamber via a first vacuum lock door and connected the second process chamber via a second vacuum lock door, the transfer chamber having a gas distribution system and a third, distinct pumping element that maintain a pressure of about 3 Torr in the transfer chamber and actively purge the transfer chamber by flowing N2 at a rate of 2 liters per minute to 7 liters per minute during the transferring of the substrate between the first process chamber, the second process chamber, and the third process chamber; and introducing the substrate to the processing system through a load lock distinct from said transfer chamber to allow introduction and removal of the substrate from the processing system.