# Initialization failed to converge charge update.

#1

Hi,

I’m working on a DEVICE transient simulation but it keeps coming up with an error message:

“Refinement limit exceeded for auto-refinement. The mesh is valid but may not be adequately refined.
Initialization failed to converge charge update.”

Especially, what does it mean by “Initialization failed to converge charge update.” and what would you suggest me to fix this problem so I can complete my simulation? Thanks a lot !

Best

#2

The first part of the message (“Refinement limit exceeded for auto-refinement. The mesh is valid but may not be adequately refined”) is a warning and is probably indicating to the source of the problem. The warning tells us that the mesh is not refined enough. The solution to this problem is discussed in this KX post.

The transient solver performs a steady state simulation for the conditions at t=0 and uses that as the initial solution for the transient simulation. The error message “Initialization failed to converge charge update” means that the steady state solution failed. This could be due to the non-refined mesh. Also, if the initial condition at t=0 (such a voltages at contacts) is far from equilibrium (large voltages) then the solver may fail to find the steady state solution as well. In such a case, you can first perform a steady state simulation and gradually sweep the voltage up to the desired level and then use that solution to initialize your transient simulation. This is described in this other KX post.

#3

Hi,

Thank you for your response. I tested the steady state simulation and it worked in 2015a version
but still failed with the same message " Initialization failed to converge charge update." in 2016a version.
I wonder that what we can do to solve this problem when this occur in the steady state simulation ?
Does it has anything to do with the 2016a version?

A lot of thanks!

#4

Can you share your project file with me so I can take a look at it?

#5

Hi,

This is the file which keep going error with message “Initialization failed to converge charge update”.

The file is too big to upload so I just attach the script which can set up my structure and simulation conditions with my optical generation exported file.

I wonder the reason for this. Thank you for your support !