Reply To: Adding Phase Shifters from demofab to Directional Coupler

[Xaveer]

Hi Aleksandar,

The phase shifter has a different cross section (“deep”) and you therefore need to add a shallow-to-deep junction. Also, placing the pad directly on top of the modulator is not advised, because the underlying structure could be damaged during electrical probing or bonding. So I added an offset w.r.t. the phase modulator.

Instead of the bend_strt_bend I used an sbend, which is usually what you’d have in such cases.

import nazca as nd
import nazca.demofab as demo

with nd.Cell("Coupler") as coupler:
    # Upper arm
    demo.shallow.sinebend(distance=100, offset=-40).put(0, 50)
    demo.shallow.strt(length=20).put()
    demo.shallow.sinebend(distance=100, offset=40).put()

    # Lower arm
    demo.shallow.sinebend(distance=100, offset=40).put(0, -50)
    demo.shallow.strt(length=20).put()
    demo.shallow.sinebend(distance=100, offset=-40).put()

    # Pins
    nd.Pin("a0").put(0, 50, 180)
    nd.Pin("a1").put(0, -50, 180)
    nd.Pin("b0").put(220, 50, 0)
    nd.Pin("b1").put(220, -50, 0)

C = coupler.put(0)
demo.s2d().put()
eopm = demo.eopm_dc(length=150).put()

pad = demo.pad_dc().put(eopm.pin["c1"].move(200, 100, 0))

demo.metaldc.sbend_p2p(eopm.pin["c1"], Lstart=100).put()

nd.export_gds()

Xaveer