Abstract: A method for fabricating semiconductor device includes the steps of: providing a substrate having a memory region and a periphery region; forming a first trench and a second trench in substrate on the memory region, in which a width of the second trench is greater than a width of the first trench; forming a first liner in the first trench and the second trench; forming a second liner on the first liner as the second liner completely fills the first trench and partly fills the second trench; and planarizing the second liner and the first liner to form a first isolation structure and a second isolation structure.

Abstract: A flash includes a substrate comprising an active region and two electron storage structures disposed at two sides of the active region, wherein each of the electron storage structures comprises a silicon oxide/silicon nitride/silicon oxide composite layer. A buried gate is embedded in the active region, wherein the buried gate only consists of a control gate and a gate dielectric layer, and the gate dielectric layer is formed by a single material. Two source/drain doping regions are disposed in the active region at two sides of the buried gate.

Abstract: A method for fabricating semiconductor device includes the steps of: providing a substrate having a memory region and a periphery region; forming a first trench and a second trench in substrate on the memory region, in which a width of the second trench is greater than a width of the first trench; forming a first liner in the first trench and the second trench; forming a second liner on the first liner as the second liner completely fills the first trench and partly fills the second trench; and planarizing the second liner and the first liner to form a first isolation structure and a second isolation structure.

Abstract: A method for fabricating semiconductor device includes the steps of: providing a substrate having a memory region and a periphery region; forming a first trench and a second trench in substrate on the memory region, wherein a width of the second trench is greater than a width of the first trench; forming a first liner in the first trench and the second trench; forming a second liner on the first liner, wherein the second liner completely fills the first trench and partly fills the second trench; and planarizing the second liner and the first liner to form a first isolation structure and a second isolation structure.

Abstract: A method of forming an isolation structure includes the following steps. A substrate having a first trench, a second trench and a third trench is provided, wherein the opening of the third trench is larger than the opening of the second trench, and the opening of the second trench is larger than the opening of the first trench. A first oxide layer is formed to conformally cover the first trench, the second trench and the third trench by an atomic layer deposition (ALD) process. A second oxide layer fills up the first trench by an in-situ steam generation (ISSG) process.

Abstract: A flash includes a substrate comprising an active region and two electron storage structures disposed at two sides of the active region, wherein each of the electron storage structures comprises a silicon oxide/silicon nitride/silicon oxide composite layer. A buried gate is embedded in the active region, wherein the buried gate only consists of a control gate and a gate dielectric layer, and the gate dielectric layer is formed by a single material. Two source/drain doping regions are disposed in the active region at two sides of the buried gate.

Abstract: A method of forming an isolation structure includes the following steps. A substrate having a first trench, a second trench and a third trench is provided, wherein the opening of the third trench is larger than the opening of the second trench, and the opening of the second trench is larger than the opening of the first trench. A first oxide layer is formed to conformally cover the first trench, the second trench and the third trench by an atomic layer deposition (ALD) process. A second oxide layer fills up the first trench by an in-situ steam generation (ISSG) process.

Abstract: A method for fabricating semiconductor device includes the steps of: providing a substrate having a memory region and a periphery region; forming a first trench and a second trench in substrate on the memory region, wherein a width of the second trench is greater than a width of the first trench; forming a first liner in the first trench and the second trench; forming a second liner on the first liner, wherein the second liner completely fills the first trench and partly fills the second trench; and planarizing the second liner and the first liner to form a first isolation structure and a second isolation structure.