Non-volatile memory device and method for fabricating the same
View Patent ↗A non-volatile memory device includes a plurality of stacked patterns where a tunnel insulation layer, a floating gate, and a dielectric layer are sequentially stacked over a substrate, trenches formed in the substrate between the stacked patterns, an isolation layer gap-filling the trenches and space between the stacked patterns, and a control gate formed over the dielectric layer.
1. A non-volatile memory device, comprising:
a plurality of stacked patterns comprising a tunnel insulation layer, a floating gate, and a dielectric layer sequentially stacked and formed over a substrate;
trenches formed in the substrate between the stacked patterns;
an isolation layer gap-filling the trenches and space between the stacked patterns; and
a control gate formed over the dielectric layer,
wherein a surface of the floating gate is aligned with a surface of the isolation layer.
2. The non-volatile memory device of claim 1 , wherein the dielectric layers of the stacked patterns are separated by the isolation layer.
3. The non-volatile memory device of claim 1 , wherein the dielectric layer comprises an insulation layer having a high dielectric rate.
4. The non-volatile memory device of claim 1 , wherein the dielectric layer is disposed over the aligned surface of the floating gate and the isolation layer.
5. A method for fabricating a non-volatile memory device, comprising:
forming a plurality of stacked patterns where a tunnel insulation layer, a floating gate, a dielectric layer, and a capping layer are sequentially stacked over a substrate;
forming trenches by etching the substrate between the stacked patterns;
forming an isolation layer gap-filling the trenches and space between the stacked patterns, wherein a surface of the capping layer is aligned with a surface of the isolation layer; and
forming a control gate over the stacked patterns.
6. The method of claim 5 , wherein the forming of the stacked patterns comprises:
forming a stacked layer by sequentially stacking the tunnel insulation layer, a floating gate conductive layer, the dielectric layer, and the capping layer over the substrate;
forming a hard mask pattern over the stacked layer; and
etching the stacked layer by using the hard mask pattern as an etch barrier.
7. The method of claim 6 , wherein in the forming of the trenches,
the substrate is etched by using the hard mask pattern as an etch barrier after the forming of the stacked patterns.
8. The method of claim 5 , wherein the forming of the isolation layer comprises:
forming an insulation layer over the substrate; and
performing a planarization process onto the insulation layer until the capping layer is exposed.
9. The method of claim 8 , wherein in the performing of the planarization process,
an etch process or a chemical mechanical polishing (CMP) process is performed alone, or a combination of the etch process and the CMP process is performed.
10. The method of claim 5 , wherein the capping layer is an insulation layer or a conductive layer.
11. The method of claim 5 , further comprising:
removing the capping layer before the forming of the control gate.
12. A method for fabricating a non-volatile memory device, comprising:
forming floating gates over active regions of a substrate;
forming an isolation layer by gap-filling spaces between the floating gates and between the active regions of the substrate, wherein surfaces of the floating gates are aligned with a surface of the isolation layer; and
forming a control gate over the aligned surface.
13. The method of claim 12 , wherein the forming of the floating gates comprises:
sequentially forming a tunnel insulation layer, a floating gate conductive layer, a dielectric layer, and a hard mask pattern over the substrate; and
etching the dielectric layer, the floating gate conductive layer, the tunnel insulation layer, and the substrate by using the hard mask pattern as an etch barrier to form the floating gates and trenches in the substrate.
14. The method of claim 12 , further comprising forming a dielectric layer over the aligned surface before the forming of the control gate.
15. A non-volatile memory device, comprising:
a plurality of stacked patterns comprising a tunnel insulation layer, a floating gate, a dielectric layer and a capping layer sequentially stacked and formed over a substrate;
trenches formed in the substrate between the stacked patterns;
an isolation layer gap-filling the trenches and space between the stacked patterns; and
a control gate formed over the stacked patterns,
wherein a surface of the capping layer is aligned with a surface of the isolation layer.
16. The non-volatile memory device of claim 15 , wherein the capping layer comprises a conductive layer.
17. The non-volatile memory device of claim 15 , wherein the dielectric layers of the stacked patterns are separated by the isolation layer.
18. The non-volatile memory device of claim 15 , wherein the dielectric layer comprises an insulation layer having a high dielectric rate.
19. The non-volatile memory device of claim 15 , wherein the control gate is disposed over the aligned surface of the capping layer and the isolation layer.