Technology Import
=================

To use KLayout and the Photonics-extension efficiently, it is recommended to create a KLayout technology. This chapter explains how to import a technology.

To use a new technology either create a new technology from the technology manager :menuselection:`Tools --> Manage Technologies` or create a new package 
:menuselection:`Tools --> Manage Packages` for the technology.

Import Techfile & Creation of LayerProperties
---------------------------------------------

KLayout provides an import script for Cadence techfiles. This import creats the Layer Properties automatically for the defined layers.

The script can be found in :menuselection:`File --> Import Cadence Techfile`

After importing, the properties can be saved via :menuselection:`File --> Save Layer Properties`. Recommended location for the file is in the technology folder in `~/.klayout/tech/<technology-name>/<file>` or if using a package
`~/.klayout/salt/<technology-package>/tech/<filename>`

.. note::
    Suggested filename for easy use with the sample cells: FreePDK45.tf / FreePDK45.lyp
    
    In order to use the additional abstract layers in the sample cells paste the following xml snippets into the <>.lyp file:
    
    .. code-block:: xml
    
        <properties>
            <frame-color>#01ff6b</frame-color>
            <fill-color>#01ff6b</fill-color>
            <frame-brightness>0</frame-brightness>
            <fill-brightness>0</fill-brightness>
            <dither-pattern>I3</dither-pattern>
            <line-style>I6</line-style>
            <valid>true</valid>
            <visible>true</visible>
            <transparent>false</transparent>
            <width>1</width>
            <marked>false</marked>
            <xfill>false</xfill>
            <animation>0</animation>
            <name>phot_silicon.drawing</name>
            <source>400/0@1</source>
        </properties>
        <properties>
            <frame-color>#808080</frame-color>
            <fill-color>#808080</fill-color>
            <frame-brightness>0</frame-brightness>
            <fill-brightness>0</fill-brightness>
            <dither-pattern>I2</dither-pattern>
            <line-style>I0</line-style>
            <valid>true</valid>
            <visible>true</visible>
            <transparent>false</transparent>
            <width>1</width>
            <marked>false</marked>
            <xfill>false</xfill>
            <animation>0</animation>
            <name>phot_poly.drawing</name>
            <source>410/0@1</source>
        </properties>
        <properties>
            <frame-color>#ff0000</frame-color>
            <fill-color>#ff0000</fill-color>
            <frame-brightness>0</frame-brightness>
            <fill-brightness>0</fill-brightness>
            <dither-pattern>I9</dither-pattern>
            <line-style/>
            <valid>true</valid>
            <visible>true</visible>
            <transparent>false</transparent>
            <width>1</width>
            <marked>false</marked>
            <xfill>false</xfill>
            <animation>0</animation>
            <name>phot_pwell.drawing</name>
            <source>420/0@1</source>
        </properties>
        <properties>
            <frame-color>#0000ff</frame-color>
            <fill-color>#0000ff</fill-color>
            <frame-brightness>0</frame-brightness>
            <fill-brightness>0</fill-brightness>
            <dither-pattern>I5</dither-pattern>
            <line-style/>
            <valid>true</valid>
            <visible>true</visible>
            <transparent>false</transparent>
            <width>1</width>
            <marked>false</marked>
            <xfill>false</xfill>
            <animation>0</animation>
            <name>phot_nwell.drawing</name>
            <source>430/0@1</source>
        </properties>
        <properties>
            <frame-color>#ff0000</frame-color>
            <fill-color>#ff0000</fill-color>
            <frame-brightness>0</frame-brightness>
            <fill-brightness>0</fill-brightness>
            <dither-pattern>I11</dither-pattern>
            <line-style/>
            <valid>true</valid>
            <visible>true</visible>
            <transparent>false</transparent>
            <width>1</width>
            <marked>false</marked>
            <xfill>false</xfill>
            <animation>0</animation>
            <name>phot_pimplant.drawing</name>
            <source>440/0@1</source>
        </properties>
        <properties>
            <frame-color>#0000ff</frame-color>
            <fill-color>#0000ff</fill-color>
            <frame-brightness>0</frame-brightness>
            <fill-brightness>0</fill-brightness>
            <dither-pattern>I7</dither-pattern>
            <line-style/>
            <valid>true</valid>
            <visible>true</visible>
            <transparent>false</transparent>
            <width>1</width>
            <marked>false</marked>
            <xfill>false</xfill>
            <animation>0</animation>
            <name>phot_nimplant.drawing</name>
            <source>450/0@1</source>
        </properties>
        
    Put this block between the last properties block but befor the end of the name block.

Import of example Vias
----------------------

Importing a .LEF will create the layerproperties. The layerproperties are the layer-purpose-pairs of KLayout. When using the lef import script built into 
KLayout, it will automatically load example vias into a new layout. Unfortunately, the layers are not the correct layers from the technology files.
The layers can be edited by selecting a layer in the layers sub-window and then editing the layer via :menuselection:`Edit --> Layer --> Edit Layer Specification`.
Recommended place is in the `~/.klayout/tech/libraries` or if using a package: `~/.klayout/salt/<package-name>/tech/libraries`. These will automatically be loaded and are available as static cells for insert or in PCells.

Layermap
--------

The .layermap file is usually supplied by the foundry. This file can be used in the pcell_lib_ext to use layernames instead of layer numbers in the PCell Library.
It contains layername | layernumber | layerdatatype on each line for each layer. They have to be separated by white spaces. Afterwards, they can by used by the `self.add_layer(str varname, str layername)`
function during the `__init__` of a new class of a PCell. Later the layer is accessible as `self.varname`.

Recommended place is again in the tech folder.