Semiconductor device and manufacturing method thereof
View Patent ↗The present invention provides a semiconductor device that reduces the junction leak current and achieves an improvement in the reliability of the gate oxide film by minimizing divot formation and the occurrence of a kink and a method of manufacturing such a semiconductor device. A pad oxide film and a silicon nitride film are formed on an Si substrate and a groove-like trench is formed through photolithography and etching. The liner oxide of the trench are oxidized through oxidizing/nitriding. Then, the trench is filled with an insulating film, the insulating film is planarized and the silicon nitride film and the pad oxide film are removed. Next, a field area is formed and a transistor is formed by following specific steps. By forming a trench liner oxide film containing nitrogen, stress is reduced.
1. A method of fabricating a semiconductor device, the method comprising:
providing a substrate;
forming a pad oxide film and a silicon nitride film over the substrate;
forming a trench;
forming a liner oxide at least in the trench by an oxidizing step, an nitriding step and another oxidizing step; and
substantially filling the trench with an insulating film, performing a planarizing step to remove the pad oxide and the silicon nitride film that are over the substrate.
2. A method of fabricating a semiconductor device, the method comprising:
providing a substrate;
forming a pad oxide film and a silicon nitride film over the substrate;
forming a trench;
forming a liner oxide at least in the trench by an oxidizing step;
substantially filling the trench with an insulating film, performing a planarizing step to remove the pad oxide and the silicon nitride film that are over the substrate;
forming a sacrificial oxide layer by performing an oxidizing step, a nitriding step and another oxidizing step; and
performing an ion implantation step.
3. A method of fabricating a semiconductor device, the method comprising:
providing a substrate;
forming a pad oxide film and a silicon nitride film over the substrate;
forming a trench;
forming a liner oxide at least in the trench by an oxidizing step, an nitriding step and another oxidizing step; and
substantially filling the trench with an insulating film, performing a planarizing step to remove the pad oxide and the silicon nitride film that are over the substrate; and
forming a sacrificial oxide layer by performing an oxidizing step, a nitriding step and another oxidizing step.
4. A method of fabricating a semiconductor device, the method comprising:
providing a substrate;
forming a pad oxide film and a silicon nitride film over the substrate;
forming a trench;
forming a liner oxide at least in the trench by an oxidizing step, an nitriding step and another oxidizing step; and
substantially filling the trench with an insulating film, performing a planarizing step to remove the pad oxide and the silicon nitride film that are over the substrate; and
forming a gate oxide by an oxidizing step, a nitriding step and another oxidizing step.
5. A method of fabricating a semiconductor device, the method comprising:
providing a substrate;
chemical vapor depositing a TEOS pad oxide film over the substrate and annealing the pad oxide film by a rapid thermal anneal step
forming a silicon nitride film over the pad oxide;
forming a trench;
forming a liner oxide at least in the trench by an oxidizing step, an nitriding step and another oxidizing step; and
substantially filling the trench with an insulating film, performing a planarizing step to remove the pad oxide and the silicon nitride film that are over the substrate; and
forming gate oxide layer by performing an oxidizing step, a nitriding step and another oxidizing step.
6. A method of fabricating a semiconductor device, the method comprising:
providing a substrate;
chemical vapor depositing a TEOS pad oxide film over the substrate and annealing the pad oxide film by a rapid thermal anneal step:
forming a silicon nitride film over the pad oxide;
etching the silicon nitride film after performing a photolithographic process;
forming a sacrificial local oxidation of silicon layer by an oxidizing step, a nitriding step and another oxidizing step and a nitriding step;
forming a trench;
forming a liner oxide at least in the trench by an oxidizing step, a nitriding step and another oxidizing step; and
substantially filling the trench with an insulating film, performing a planarizing step to remove the pad oxide and the silicon nitride film that are over the substrate; and
forming gate oxide layer by performing an oxidizing step, a nitriding step and another oxidizing step.