Patent ID: 11874540
Assignee: UNIVERSITY OF SOUTHAMPTON
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 23:
24. A method of fabricating a resonator modulator of claim 1, the method comprising the following steps:
providing a substrate, the substrate comprising a semiconductor layer on a underlaying layer on a semiconductor substrate layer;
depositing or growing an insulating layer onto the semiconductor layer,
etching through the insulating layer and the semiconductor layer to the underlaying layer to form an outer trench and an inner disk of crystalline material, the inner disk comprising an outer wall surrounded by the outer trench;
depositing or growing an insulating material onto the outer wall to form a ring-shaped insulating region;
depositing a polycrystalline semiconductor material onto the ring-shaped insulating region to fill the outer trench and cover the insulating layer, and
a planarising step comprising removing a portion of the polycrystalline semiconductor material down to the level of the insulating layer to form a capacitor comprising the ring-shaped insulating region sandwiched between an outer conductive region and an inner conductive region, wherein the outer conductive region is formed of the polycrystalline semiconductor material and the inner conductive region is formed of the crystalline material.