Skip to main content

PDK factory for klayout

Project description


This is a pure-python PDK factory that enables klayout scripted layout. It assists in photonic integrated circuit layout, which relies on having specialized curved waveguides and non-square-corner shapes.


This package is heavily based on python's klayout package, still in beta version as of this writing (Jul 2019).

Installation with pip (virtual environment is highly recommended):

pip install zeropdk

Installation from source:

python install


KLayout extension

By importing zeropdk, klayout is patched with a few useful functionalities. For example:

import klayout.db as kdb
import zeropdk

layout = kdb.Layout()
plogo = layout.read_cell(cell_name='princeton_logo', filepath='gdslibrary/princeton_logo_simple.gds')

# plogo is a cell in the current layout. It can be inserted in the top cell.

Easy technology layers definition

Based on a KLayout's layout properties file (.lyp) containing layer definitions, it is easy to import and use all layers. For example:

from zeropdk import Tech
lyp_path = "examples/EBeam.lyp"
EBeam = Tech.load_from_xml(lyp_path)
layerM1 = EBeam.layers["M1"]
print(layerM1, type(layerM1))  # M1 (41/0) <class 'klayout.dbcore.LayerInfo'>

The file above belongs to a project called SiEPIC EBeam PDK, used in passive silicon photonic foundries.

Advanced PCell definition

PCells can be hierarchical, as described in Sec. IV.C of this article. One PCell can use another PCell in its definition, and the parent pcell should, in this case, inherit the child's parameters. an example taken from is:

class DCPadArray(DCPad):
    params = ParamContainer(pad_array_count, pad_array_pitch)

    def draw(self, cell):
        # ...
        for i in range(cp.pad_array_count):
            dcpad = DCPad(name=f"pad_{i}", params=cp)
        return cell, ports

In this case, DCPadArray simply places an array of DCPad Pcells, and contains parameters pad_array_count and also pad_array_pitch, but also the parameters belonging to DCPad, such as layer_metal and layer_opening.

In the EBeam PDK example, one can edit adapt a standard library of pcells to its own parameter sets. For example, EBeam PDK uses particular layers for its metal deposition and oxide etch steps. So the DCPadArray can be changed via the following:

class DCPadArray(DCPadArray):
    params = ParamContainer(
            description="Metal Layer",
            description="Open Layer",

TODO: adapt example provided here to zeropdk.

Photonics-inspired layout functions

Several assistive tools for handling photonic shapes. For example, it is desired, sometimes, to draw a waveguide with progressive widths (a taper).

from zeropdk.layout import layout_waveguide
wav_polygon = layout_waveguide(cell, layer, points_list, width)

Developer notes

This project is still under development phase. See the development notes for more information.

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for zeropdk, version 20.10b0
Filename, size File type Python version Upload date Hashes
Filename, size zeropdk-20.10b0-py3-none-any.whl (90.8 kB) File type Wheel Python version py3 Upload date Hashes View

Supported by

Pingdom Pingdom Monitoring Google Google Object Storage and Download Analytics Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page