Infrared Reflectometry For Metrology Of Trenches In Power Devices

We present examples of the application of Model- Based Infrared Reflectometry (MBIR) to metrology of trench-based power devices at different stages in the fabrication process. These metrology problems are similar to those encountered during the fabrication of deep trench memory devices, but pose some new challenges. We propose analysis methods that overcome the challenges and produce data useful for process control in fabrication facilities. The results indicate that MBIR can become a powerful metrology tool in a variety of applications during the fabrication of silicon power devices.