% Quokka3 example settingsfile for a circular TLM structure
% (c) 2019 Andreas Fell
%
% shows how to use probes to sense surface potential in order to accurately simulate a 4PP measurement
% the 4 probes are placed in a line with a distance of 500µm each (~ fixed 4PP head)

Syntax = 'generic';

Domain.DeviceType = 'ohmic device';
Domain.Dimensions = 3;
Domain.Wx = 4e3;
Domain.Wy = 4e3;
Domain.Wz = 200; % wafer thickness

Solver.SolutionType = 'Resistance';
Solver.Electrical.MetalModelType = 'finite-differences'; % 'finite-differences' required to account for current pins, otherwise for 'constant-potential' there is no potential drop within metal features
Solver.ExternalCircuit.Enable = 0;
Solver.Sweep.Enable = 1; %

Sweep.NGroups = 2;
Sweep.GroupA(1).Parameter = 'ContactFeature(2).Geometry.SizeX';
Sweep.GroupA(1).Values = [1200:100:1700];
Sweep.GroupA(2).Parameter = 'MetalFeature(2).Geometry.SizeX';
Sweep.GroupA(2).Values = [1200:100:1700];
Sweep.GroupB(1).Parameter = 'ContactFeature(1).OhmicResistivity';
Sweep.GroupB(1).Values = [1e-4 1e-3 1e-2];
Sweep.GroupB(2).Parameter = 'ContactFeature(2).OhmicResistivity';
Sweep.GroupB(2).Values = [1e-4 1e-3 1e-2];

Bulk.Mesh.Quality = 'standard'; % at least 'standard' to resolve the circle, grid-independency should be checked!
Bulk.Electrical.BackgroundDoping.Resistivity = 2; % set very high to not consider current transport through the bulk (e.g. due to a pn-junction being present at the front)

SkinFeature(1).Name = 'full area skin'; % front skin, e.g. an emitter diffusion
SkinFeature(1).Geometry.Plane = 'front';
SkinFeature(1).Geometry.Shape = 'full';
SkinFeature(1).Lumped.Electrical.RsheetEnable = 1;
SkinFeature(1).Lumped.Electrical.Rsheet = 100;

ContactFeature(1).Name = 'outer contact';
ContactFeature(1).Geometry.Plane = 'front';
ContactFeature(1).Geometry.Shape = 'circle';
ContactFeature(1).Geometry.Inverse = 1; % defines a contact everywhere except of this circle
ContactFeature(1).Geometry.PositionX = 2e3;
ContactFeature(1).Geometry.PositionY = 2e3;
ContactFeature(1).Geometry.SizeX = 1800; % outer circle diameter
ContactFeature(1).OhmicResistivity = 3e-3; % this is the contact resistivity of interest

ContactFeature(2).Name = 'inner contact';
ContactFeature(2).Geometry.Plane = 'front';
ContactFeature(2).Geometry.Shape = 'circle';
ContactFeature(2).Geometry.PositionX = 2e3;
ContactFeature(2).Geometry.PositionY = 2e3;
ContactFeature(2).Geometry.SizeX = 1200; % inner circle diameter
ContactFeature(2).OhmicResistivity = 3e-3; % this is the contact resistivity of interest

MetalFeature(1).Name = 'outer metal';
MetalFeature(1).Geometry.Plane = 'front';
MetalFeature(1).Geometry.Shape = 'circle';
MetalFeature(1).Geometry.Inverse = 1;
MetalFeature(1).Geometry.PositionX = 2e3;
MetalFeature(1).Geometry.PositionY = 2e3;
MetalFeature(1).Geometry.SizeX = 1800; % diameter
MetalFeature(1).Electrical.Polarity = 'n-type'; % this defines the potential applied to this metal feature ('n-type' = 1V), must only be given for 'constant-potential' metal model type
MetalFeature(1).Electrical.Rsheet = 1; % only required for 'finite-differences' metal model type

MetalFeature(2).Name = 'inner metal';
MetalFeature(2).Geometry.Plane = 'front';
MetalFeature(2).Geometry.Shape = 'circle';
MetalFeature(2).Geometry.PositionX = 2e3;
MetalFeature(2).Geometry.PositionY = 2e3;
MetalFeature(2).Geometry.SizeX = 1200; % diameter
MetalFeature(2).Electrical.Polarity = 'p-type'; % this defines the potential applied to this metal feature ('p-type' = 0V), must only be given for 'constant-potential' metal model type
MetalFeature(2).Electrical.Rsheet = 1; % only required for 'finite-differences' metal model type

PadFeature(1).Name = 'current pin 1'; % pin in the center
PadFeature(1).Geometry.Plane = 'front';
PadFeature(1).Geometry.Shape = 'rectangle';
PadFeature(1).Geometry.PositionX = 2e3;
PadFeature(1).Geometry.PositionY = 2e3;
PadFeature(1).Geometry.SizeX = 30;
PadFeature(1).Geometry.SizeY = 30;
PadFeature(1).Electrical.Polarity = 'n-type'; % 1V
PadFeature(1).Electrical.ContactResistivity = 1e-5; % negligible low, but do not set it to 0!

PadFeature(2).Name = 'current pin 2'; % pin on the outer metal
PadFeature(2).Geometry.Plane = 'front';
PadFeature(2).Geometry.Shape = 'rectangle';
PadFeature(2).Geometry.PositionX = 3.5e3;
PadFeature(2).Geometry.PositionY = 2e3;
PadFeature(2).Geometry.SizeX = 30;
PadFeature(2).Geometry.SizeY = 30;
PadFeature(2).Electrical.Polarity = 'p-type'; % 0V
PadFeature(2).Electrical.ContactResistivity = 1e-5; % contact resistivity between metal and pin

Probe(1).Name = 'voltage pin 1'; % voltage pin 500µm right of current pin 1
Probe(1).Plane = 'front';
Probe(1).PositionX = 2.5e3;
Probe(1).PositionY = 2e3;

Probe(2).Name = 'voltage pin 2'; % voltage pin 1000µm right of current pin 1
Probe(2).Plane = 'front';
Probe(2).PositionX = 3e3;
Probe(2).PositionY = 2e3;