Fabrication method for a silicon nitride read-only memory
AssigneeMacronix International Co., Ltd.
InventorsChien-Hung Liu, Shyi-Shuh Pan, Shou-Wei Huang
Life of this patent
Estimating the term…
Abstract
A fabrication method for a read-only memory with a silicon nitride floating gate is provided. A first oxide layer and a silicon nitride layer are sequentially formed on a substrate. The silicon nitride layer and the first oxide layer are then patterned to form an opening, exposing a portion of the substrate. An oxidation process is then conducted to form a second oxide layer on the silicon nitride layer and concurrently to form a field oxide layer on the exposed substrate. The second oxide layer, the silicon nitride layer and the first oxide layer are then patterned to form an oxide dielectric layer, a silicon nitride floating gate layer and a tunnel oxide layer.
Claims21
A method for fabricating a silicon nitride floating gate for a read-only memory, comprising:
- providing a substrate;
- forming a first oxide layer on the substrate;
- forming a silicon nitride layer on the first oxide layer;
- patterning the silicon nitride layer and the first oxide layer to form an opening, exposing a portion of the substrate;
- forming concurrently a second oxide layer on the silicon nitride layer and a field oxide layer on the substrate exposed by the opening;
- and
- patterning the second oxide layer, the silicon nitride layer and the first oxide layer to form an oxide dielectric layer, a silicon nitride floating gate layer and a tunnel oxide layer.
A method for fabricating a read-only memory, comprising:
- providing a substrate;
- forming a first oxide layer and a material layer on the substrate, wherein a portion of the substrate is not covered by the first oxide layer and the material layer;
- and
- forming concurrently a second oxide layer on the material layer and a third oxide layer on the exposed substrate.
Dependencies are inferred from the claim text.