Method of manufacturing a piezoelectric transistor
View Patent ↗According to the present application, a method of manufacturing a piezoelectric transistor may include forming a cavity over a substrate, such as a semiconductor substrate. The method may include depositing and patterning metal material over a portion of a cavity, and may include depositing an oxide film over a cavity and/or patterned metal material. Piezoelectric material may be deposited over an oxide film and patterned to avoid connection with metal material. The method may include depositing a second oxide film over a substrate including piezoelectric material. Metal wiring may be formed and may apply voltage to piezoelectric material that may be in contact with a semiconductor substrate.
1. A method comprising:
forming a cavity over a substrate;
depositing a metal material over at least a portion of the cavity;
depositing a piezoelectric material disconnected from the metal material; and
forming a metal wiring configured to apply voltage to the piezoelectric material,
wherein the piezoelectric material moves downward and contacts the metal material by a piezoelectric effect.
2. The method of claim 1 , wherein the substrate comprises semiconductor material.
3. The method of claim 1 , comprising:
wherein depositing the metal material includes:
patterning the metal material; and
depositing a first oxide film over the cavity and the patterned metal material, and
wherein depositing the piezoelectric material includes:
depositing the piezoelectric material over the first oxide film;
patterning the piezoelectric material; and
depositing a second oxide film over the substrate.
4. The method of claim 3 , wherein at least one of the first oxide film and the second oxide film comprises a relatively low temperature oxide film.
5. The method of claim 3 , wherein the piezoelectric material is in contact with the substrate.
6. The method of claim 5 , wherein forming the metal wiring comprises:
forming a via over the second oxide film where the piezoelectric material is in contact with the substrate;
depositing a metal over the via and the second oxide film to form a first metal wiring;
patterning the first metal wiring;
forming an inter metal dielectric layer over the patterned first metal wiring;
forming a via over the inter metal dielectric layer; and
depositing metal over the via and the inter metal dielectric layer to form a second metal wiring.
7. The method of claim 6 , wherein the inter metal dielectric layer comprises Tetra-ethyl ortho-silicate.
8. The method of claim 1 , wherein the cavity is formed by at least one of a reactive ion etching and a wet etching process.
9. The method of claim 1 , wherein:
the metal wiring comprises aluminum; and
the piezoelectric material comprises at least one of lead zirconate titanate and barium titanate.