"""Via chain."""
from __future__ import annotations
import gdsfactory as gf
from gdsfactory.component import Component
from gdsfactory.components.via import via1
from gdsfactory.components.via_stack import via_stack_m2_m3
from gdsfactory.typings import ComponentSpec, LayerSpecs
[docs]
@gf.cell
def via_chain(
num_vias: int = 100,
cols: int = 10,
via: ComponentSpec = via1,
contact: ComponentSpec = via_stack_m2_m3,
layers_bot: LayerSpecs = ("M1",),
layers_top: LayerSpecs = ("M2",),
offsets_top: tuple[float, ...] = (0,),
offsets_bot: tuple[float, ...] = (0,),
via_min_enclosure: float = 1.0,
min_metal_spacing: float = 1.0,
via_xoffset: float = 0.0,
via_yoffset: float = 0.0,
) -> Component:
"""Via chain to extract via resistance.
Args:
num_vias: number of vias.
cols: number of column pairs.
via: via component.
contact: contact component.
layers_bot: list of bottom layers.
layers_top: list of top layers.
offsets_top: list of top layer offsets.
offsets_bot: list of bottom layer offsets.
via_min_enclosure: via_min_enclosure.
min_metal_spacing: min_metal_spacing.
via_xoffset: horizontal offset of the vias.
via_yoffset: vertical offset of the vias.
.. code::
side view:
min_metal_spacing
┌────────────────────────────────────┐ ┌────────────────────────────────────┐
│ layers_top │ │ │
│ │◄───────────► │ │
└─────────────┬─────┬────────────────┘ └───────────────┬─────┬──────────────┘
│ │ via_enclosure │ │
│ │◄───────────────► │ │
│ │ │ │
│ │ │ │
│width│ │ │
◄─────► │ │
│ │ │ │
┌─────────────┴─────┴───────────────────────────────────────────────┴─────┴───────────────┐
│ layers_bot │
│ │
└─────────────────────────────────────────────────────────────────────────────────────────┘
◄─────────────────────────────────────────────────────────────────────────────────────────►
2*e + w + min_metal_spacing + 2*e + w
"""
if cols % 2 != 0:
raise ValueError(f"{cols=} must be even")
c = gf.Component()
rows = num_vias / cols
if int(rows) != rows:
raise ValueError(f"{num_vias=} must be a multiple of {cols=}")
if rows <= 1:
raise ValueError(
f"rows must be at least 2. Got {rows=}. You can increase the number vias {num_vias=}."
)
if rows % 2 != 0:
raise ValueError(
f"{rows=} must be even. Number of vias needs to be a multiple of {2*cols=}."
)
via = gf.get_component(via)
contact = gf.get_component(contact)
wire_length = 2 * (2 * via_min_enclosure + via.size_info.width) + min_metal_spacing
via_width = via.size_info.width
wire_width = via_width + 2 * via_min_enclosure
wire_size = (wire_length, wire_width)
via_spacing = (
2 * via_min_enclosure + min_metal_spacing + via.size_info.width,
wire_width + min_metal_spacing,
)
vias = c.add_array(
component=via,
columns=cols,
rows=rows,
spacing=via_spacing,
)
top_wire = gf.c.rectangles(size=wire_size, layers=layers_top, offsets=offsets_top)
top_wires = c.add_array(
component=top_wire,
columns=cols // 2,
rows=rows,
spacing=(wire_length + min_metal_spacing, wire_width + min_metal_spacing),
)
bot_wire = gf.c.rectangles(size=wire_size, layers=layers_bot, offsets=offsets_bot)
bot_wires = c.add_array(
component=bot_wire,
columns=cols // 2,
rows=rows,
spacing=(wire_length + min_metal_spacing, wire_width + min_metal_spacing),
)
top_wires.x = 0
bot_wires.xmin = (
top_wires.xmin + wire_length / 2 + min_metal_spacing / 2 - via_xoffset
)
bot_wires.y = 0
top_wires.y = 0
vias.xmin = top_wires.xmin + via_min_enclosure + via_spacing[0]
vias.ymin = top_wires.ymin + via_min_enclosure + via_yoffset
vertical_wire_left = gf.c.rectangle(
size=(2 * via_min_enclosure + via_width, 2 * wire_width + min_metal_spacing),
layer=layers_top[0],
)
right_wires = c.add_array(
component=vertical_wire_left,
columns=1,
rows=rows // 2,
spacing=(wire_width + min_metal_spacing, 2 * (wire_width + min_metal_spacing)),
)
right_wires.xmax = vias.xmax + via_min_enclosure
right_wires.y = 0
left_wires = c.add_array(
component=vertical_wire_left,
columns=1,
rows=rows // 2 - 1,
spacing=(wire_width + min_metal_spacing, 2 * (wire_width + min_metal_spacing)),
)
left_wires.xmin = top_wires.xmin
left_wires.y = 0
contact1 = c << contact
contact2 = c << contact
contact1.xmax = top_wires.xmin
contact2.xmax = top_wires.xmin
contact1.ymax = top_wires.ymin + wire_width
contact2.ymin = top_wires.ymax - wire_width
c.add_port(name="e1", port=contact1.ports["e1"])
c.add_port(name="e2", port=contact2.ports["e1"])
return c
if __name__ == "__main__":
c = via_chain(num_vias=40)
c.show(show_ports=True)
