Q&A item

Go to the Options->Recommended Parameters->Experimental Tab. Press the Modify Resist button. Here you can type your Resist Name, your measured Constant and press SaveCFG button to save data to nmaker.cfg file. If you will look at the data in this file (the only one such file in program folder) in any text editor, you will see the section:
[RESISTDATA]
Index=0
Number=2
ResistName.1=PMMA (10-40 KV)
Const.1=7.500000

Data for PMMA resist initially are taken from recom.cfg file. These are experimental data. We did a number of experiments (alpha tests) at different resist thicknesses and accelerated voltages to define the Alpha and then calculate the Constant. This technique was described in article which is published at our site.

So, using the experimental resist data, you can go to Proximity->Correction... dialog. Press Recommended... button to open Recommended Parameters->Experimental Tab. Enter desired Beam Size, Accelerated Voltage, Resist Name, Substrate Name and H0 (H0 is the Resist Thickness) and you will get the proximity function parameters - Alpha, Beta, Eta. Press OK button to return to Proximity->Correction... dialog. Now, press Set button and you will get the recommended Alpha, Beta, Eta parameters ready to use for proximity correction of your structure.

So, this is a simple way but not in your case because of absence of the experimental resist data.

As you can see, we need three proximity function parameters - Alpha, Beta, Eta for proximity correction. If you don't have these parameters measured in experiment, you can compute them by Monte Carlo calculation. If you didn’t buy the Monte Carlo option with NanoMaker we can calculate the parameters for you.
To start calculation, you need to introduce initial data:
For that, you need to know the chemical formula of the resist and its density (kg/m^3). Also, it is good to have information about other material layers (prime layer, substrate, all thicknesses and so on) and accelerating voltage, you are going to use.