Substantially planar electronic devices and circuits
A method of manufacturing a substantially planar electronic device is disclosed. The method employs a resist having three different thicknesses used for defining different structures in a single masking step. Exemplary structures are substantially planar transistors having side-gates and diodes.
1. A method of manufacturing a substantially planar electronic device comprising a first terminal, a second terminal, and a semiconductor channel providing a current flow path via which current can flow from the first terminal to the second terminal, the method comprising:
providing a first structure comprising a substrate, a layer of semiconductor material supported by the substrate, and a layer of conductor material covering the layer of semiconductor material;
processing the first structure to form a second structure comprising said substrate, a first terminal region comprising a first portion of the layer of semiconductor material covered by a first portion of the layer of conductor material, a second terminal region comprising a second portion of the layer of semiconductor material covered by a second portion of the layer of conductor material, a third portion of the layer of semiconductor material providing a semiconductor channel connecting the first and second terminal regions, and a plurality of insulative features interrupting the layer of semiconductor material and defining at least a position of the semiconductor channel;
forming a layer of photoresist material over the second structure to cover the first and second terminal regions, the third portion of the layer of semiconductor material providing the semiconductor channel, and the insulative features to form a third structure;
exposing the third structure to electromagnetic radiation from a direction such that the first and second portions of the layer of conductor material act to shield overlying portions of the layer of photoresist material from the radiation;
removing an exposed portion of the layer of photoresist material to form a window through said layer of photoresist material;
depositing dielectric material at least within said window to form a layer of dielectric material filling the insulative features and covering, either directly or indirectly, the third portion of the layer of semiconductor material providing the semiconductor channel; and
removing remaining material of the layer of photoresist material to expose the first and second portions of the layer of conductor material, the first and second portions of the layer of conductor material providing the first and second terminals respectively and being separated from each other in at least one area by the layer of dielectric material.
2. An electronic device in accordance with claim 1 , the device comprising a semiconductor channel, a dielectric layer covering the channel, and a layer of hydrophobic material covering the dielectric layer.
3. The electronic device in accordance with claim 2 , wherein the electronic device is connected within an electronic circuit.