Lab IC: Photolithography and Oxide Etching

Your goals this week are to develop an optimum photolithography procedure and determine oxide etch rates.

I. Photolithography

  1. Begin withpieces of previuosly oxidized silicon. Coat with photoresist and softbake as instructed in the photolithography procedure. Based on your previous lab choose the spin speed that will deposit ~1.5 microns of photoresist.
  2. Optimize the photlithography procedure. There are two important time constants that you will be able to adjust: exposure time and developing time. Both are very important. Look at exposure time between 1 and 5 minutes. Developing times could range from 10 to 100 seconds.
  3. The way that you will assess your results is by inspection under the optical microscope.
  4. Once you have determined your optimum conditions coat two of your oxide films, pattern and etch using BOE as described below.
  5. After the etch ash the photresist using the RIE and characterize the morphology with the surface profiler

 

II.  Oxide Etching

  1. Characteroze your oxide thickness and then determine the etch rate by measuring the etching time in BOE.