| Popis: |
Insulating materials such as photoresists retain charges during electron or ion exposure. The ultimate performances of techniques such as scanning electron microscopy (SEM), trilayer e‐beam lithography, or plasma etching can be strongly affected by this phenomenon: observations of highly resolved resist patterns and the subsequent dimensional measurements by SEM are limited by significant charge effects; resist charge during trilayer electron‐beam exposure can produce considerable pattern placement errors; surface charging is also reported to damage etching profiles and to produce microloading effects during plasma etching. Techniques such as metal deposition, use of intrinsically conducting polymers, or Ar+ or H+ high energy implantation are mentioned among others for reducing the electrical resistance of the photoresist patterns. However, due to several major drawbacks (metallic contamination, nonavailability of materials, and global cost of the process), none of these methods has been accepted today at... |
