Error: no area for degenerate linear planar polygons



Dear Ahsan,

"No area for degenerate linear planar polygon"
The previous error appears when run my structure. I tried more and more to solve it by reading about this error but I didn’t. So, I attached my structure to find where my mistake.

thank you

Avalanche Photodetectors (Carrier multiplication simulation)

Thanks for sharing the file. This particular error message is generated when the solver has problem creating the 3D geometry. A few suggestions to solve geometry building issues in DEVICE are discussed here: Geometry building issue in 3D simulation for DEVICE. Unfortunately when this problem arises, finding a solution by following these steps is not always easy and may require a lot of tweaking. In your file, I was able to make it work by taking the following steps:

  1. The bottom and top rectangles (metal) had the same span as the cone and the circle. This can create a tough situation for the solver where the edges of the curved surface aligned with the flat edge of the rectangles. To solve this issue I have made the span of the rectangles larger (which should not affect the result).

  2. The top circle was not overlapping with the top metal. I have used a slight overlap there.

  3. I have used mesh order to ensure that the top and bottom rectangle cut out from the semiconductor region by using a mesh order of 1 for the metals.

These changes helped the solver to create the geometry and mesh it. The modified file is too large so I will email it to your inbox.

NOTE: I also shifted the top (imported) doping object slightly higher to ensure that the top surface of the semiconductor gets doped.


Dear Ahsan,

Thank you for your efforts.
However, I still have the same error. The below message appears when it runs. Could you help me?


Are you using the latest version of DEVICE (v.5.1.982)? If not then upgrading to the latest version might help. You can download the latest version from here: