Semiconductor device and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-2016379985-A1
Application number	US-201615191552-A
Country	US
Kind code	A1
Filing date	Jun 24, 2016
Priority date	Jun 24, 2015
Publication date	Dec 29, 2016
Grant date	—

Abstract

A method for manufacturing a semiconductor device includes forming a storage node hole passing through an upper support layer, a bowing prevention layer and an upper mold layer using a dry etching process, forming a lower electrode in the storage node hole, patterning the upper support layer and the bowing prevention layer to expose a portion of the upper mold layer, removing the upper mold layer and at least a portion of the bowing prevention layer using a first wet etching process, and sequentially forming a dielectric layer and an upper electrode that cover the lower electrode. An etch rate of the bowing prevention layer may be substantially equal to an etch rate of the upper support layer during the dry etching process. An etch rate of the bowing prevention layer may be higher than an etch rate of the upper support layer during the first wet etching process.

First claim

What is claimed is:

1 . A method for manufacturing a semiconductor device, the method comprising:
sequentially forming an upper mold layer, a bowing prevention layer, and an upper support layer on a substrate; forming a storage node hole using a dry etching process, the storage node hole passing through the upper support layer, the bowing prevention layer and the upper mold layer; forming a lower electrode in the storage node hole; patterning the upper support layer and the bowing prevention layer to expose a portion of the upper mold layer; removing the upper mold layer and at least a portion of the bowing prevention layer using a first wet etching process; and sequentially forming a dielectric layer and an upper electrode that cover the lower electrode, wherein a first etch rate of the bowing prevention layer is substantially equal to a first etch rate of the upper support layer during the dry etching process, wherein a second etch rate of the bowing prevention layer is higher than a second etch rate of the upper support layer during the first wet etching process, and wherein the upper support layer and bowing prevention layer each have a substantially uniform thickness, and a sum of a thickness of the upper support layer and a thickness of the bowing prevention layer has a value within a range from 15% to 25% of a depth of the storage node hole.

2 . The method of claim 1 , wherein the upper support layer has a substantially uniform thickness, and the thickness of the upper support layer has a value with the range from 7% to 14% of the depth of the storage node hole.

3 . The method of claim 1 , wherein the second etch rate of the bowing prevention layer is a rate within a range from 20 times to 500 times the second etch rate of the upper support layer during the first wet etching process.

4 . The method of claim 3 , wherein the second etch rate of the bowing prevention layer is a rate within a range from 50 nm/min to 500 nm/min during the first wet etching process.

5 . The method of claim 3 , wherein the second etch rate of the upper support layer is a rate within a range from 1 nm/min to 2.5 nm/min during the first wet etching process.

6 . The method of claim 3 , wherein an etch rate of the upper mold layer is a rate within a range from the same as to up to 20 times the second etch rate of the bowing prevention layer during the first wet etching process.

7 . The method of claim 1 , wherein the bowing prevention layer is formed of a different material from that of the upper support layer, and includes Si (1-x) N x , where 0.51<x<0.55.

8 . The method of claim 1 , wherein the lower electrode forms a capacitor that is part of a memory cell including at least one transistor formed in part by a doped region in the substrate.

9 . The method of claim 7 , wherein the upper support layer includes silicon carbonitride (SiCN).

10 . The method of claim 1 , further comprising:
sequentially forming a lower mold layer and a lower support layer on the substrate before forming the upper mold layer, wherein the storage node hole passes through the upper support layer, the bowing prevention layer, the upper mold layer, the lower support layer, and the lower mold layer.

11 . The method of claim 10 , further comprising:
patterning the lower support layer to expose a portion of the lower mold layer; and removing the lower mold layer using a second wet etching process before forming the dielectric layer, wherein a portion of the bowing prevention layer remains after the first wet etching process, and wherein the portion of the bowing prevention layer remaining after the first wet etching process is removed by the second wet etching process.

12 . A method for manufacturing a semiconductor device, the method comprising:
sequentially forming an upper mold layer, a bowing prevention layer, and an upper support layer on a substrate; forming a storage node hole passing through the upper support layer, the bowing prevention layer, and the upper mold layer; forming a lower electrode in the storage node hole; patterning the upper support layer and the bowing prevention layer to expose a portion of the upper mold layer; removing the upper mold layer and at least a portion of the bowing prevention layer; and sequentially forming a dielectric layer and an upper electrode that cover the lower electrode, wherein the bowing prevention layer includes Si (1-x) N x , where 0.51<x<0.55, and wherein the upper support layer includes silicon carbonitride (SiCN).

13 . The method of claim 12 , wherein forming the storage node hole comprises: performing a dry etching process, and
wherein a first etch rate of the bowing prevention layer is substantially equal to a first etch rate of the upper support layer during the dry etching process.

14 . The method of claim 12 , wherein removing the upper mold layer and the at least a portion of the bowing prevention layer comprises: performing a wet etching process, and
wherein a second etch rate of the bowing prevention layer ranges from 20 times to 500 times a second etch rate of the upper support layer during the wet etching process.

15 . The method of claim 14 , wherein an etch rate of the upper mold layer is a rate within a range from the same as to up to 20 times the second etch rate of the bowing prevention layer during the wet etching process.

16 . The method of claim 12 , wherein the lower electrode forms a capacitor that is part of a memory cell including at least one transistor formed in part by a doped region in the substrate.

17 . A method for manufacturing a semiconductor device, the method comprising:
providing a semiconductor substrate, the semiconductor substrate including doped regions for forming transistors; forming a first insulating layer on the semiconductor substrate; forming a plurality of contact plugs extending vertically from a top surface of the first insulating layer to respective doped regions on the semiconductor substrate; sequentially forming a first mold layer, a first support layer, a second mold layer, a second support supplemental layer, and a second support layer on the first insulating layer; forming a plurality of storage node holes passing through the second support layer, the second support supplemental layer, the second mold layer, the first support layer, and the first mold layer using a dry etching process; forming a plurality of lower electrodes in corresponding each of the plurality of storage node holes; removing the second mold layer and at least portion of the second support supplemental layer using a first wet etching process; removing the first mold layer using a second wet etching process; and sequentially forming a dielectric layer and an upper electrode that cover the plurality of lower electrodes, wherein each of the plurality of storage node holes is formed over the first insulating layer and a corresponding contact plug of the plurality of contact plugs.

18 . The method of claim 17 , wherein a first etch rate of the second support supplemental layer is a rate within a range from 50 nm/min to 500 nm/min during the first wet etching process, and
wherein a first etch rate of the second support layer is a rate within a range from 1 nm/min to 2.5 nm/min during the first wet etching process.

19 . The method of claim 17 , wherein an etch rate of the second support supplemental layer is substantially equal to an etch rate of the second support layer during the dry etching process, and
wherein an etch rate of

Assignees

• Samsung Electronics Co Ltd

Inventors

• Choi Youn-Seok
• Ko Young-Min
• Kim Honggun
• Lee Jongmyeong
• Choi Byoungdeog

Classifications

• H10P50/283

  by chemical means · CPC title

• H10P50/73

  using masks for insulating materials · CPC title

• H10D1/716 Primary

  having vertical extensions · CPC title

• H01L21/31138

  Electricity · mapped topic

• H01L27/10855 Primary

  Electricity · mapped topic