Method for fabricating capacitor in semiconductor device

• US 20040126964A1
• Filed: 08/05/2003
• Published: 07/01/2004
• Est. Priority Date: 12/30/2002
• Status: Abandoned Application

• Current Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Original Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Inventors: Park, Jong-Bum, Kim, Kyong-Min, Oh, Hoon-Jung
• Application Number:
  US10/635,811
• Publication Number:
  US 20040126964A1
• Time in Patent Office: Days
• US Class Current: 438/253
• CPC Class Codes: H01L 21/022 the layer being a laminate, i.e. composed of sublayers, e.g. stacks of alternating high-k metal oxides adhesion layers or buffer layers H01L21/02304, H01L21/02362
• CPC Class Codes: H01L 21/0223 formation by oxidation, e.g. oxidation of the substrate
• CPC Class Codes: H01L 21/02247 formation by nitridation, e.g. nitridation of the substrate
• CPC Class Codes: H01L 21/02255 formation by thermal treatment H01L21/02252 takes precedence; after treatment of an insulating film H01L21/3105 and subgroups
• CPC Class Codes: H01L 21/3144 on silicon
• CPC Class Codes: H01L 21/32105 Oxidation of silicon-containing layers
• CPC Class Codes: H01L 21/3211 Nitridation of silicon-containing layers
• CPC Class Codes: H01L 28/55 with a dielectric comprising a perovskite structure material
• CPC Class Codes: H01L 28/91 made by depositing layers, e.g. by depositing alternating conductive and insulating layers
• CPC Class Codes: H10B 12/033 the capacitor extending over the transistor

Abstract

A method for fabricating a capacitor of a semiconductor device for improving a capacitance and concurrently enhancing a leakage current characteristic and a breakdown voltage characteristic. The method includes the steps of: (a) forming a conductive silicon layer for a bottom electrode on a substrate; (b) nitridating the conductive silicon layer; (c) oxidizing the nitridated conductive silicon layer; (d) forming a silicon nitride layer on a surface of the oxidized layer; (e) forming a dielectric layer on the silicon nitride layer; and (f) forming a top electrode on the dielectric layer.

Claims

1. A method for fabricating a capacitor of a semiconductor device, comprising the steps of:

(a) forming a conductive silicon layer for a bottom electrode on a substrate;

(b) nitridating the conductive silicon layer;

(c) oxidizing the nitridated conductive silicon layer;

(d) forming a silicon nitride layer on a surface of the oxidized layer;

(e) forming a dielectric layer on the silicon nitride layer; and

(f) forming a top electrode on the dielectric layer.

2. The method as recited in claim 1, wherein at the step (c), a native oxide layer is used.

3. The method as recited in claim 2, wherein the native oxide layer is formed in a thickness ranging from about 1 Å

to about 5 Å

.

4. The method as recited in claim 3, wherein at the step (b), a thermal treatment process is carried out in an atmosphere of NH₃ gas and at a pressure ranging from about 10 Torr to about 100 Torr.

5. The method as recited in claim 4, wherein the silicon nitride layer is formed by using a source of dichlorosilane (DCS) in an atmosphere of NH₃ gas and at a pressure ranging from about 1 Torr to about 10 Torr.

6. The method as recited in claim 3, wherein the dielectric layer is comprised of a material having one of a high dielectric constant and being a ferroelectric substance.

7. The method as recited in claim 6, wherein the material is one selected from a group of Ta₂O₅, Al₂O₃, HfO₂, (Ba,Sr)TiO₃ (BST), (Pb,Zr)TiO₃ (PZT), (Pb,La)(Zr,Ti)O₃ (PBZT) and Bi₄—

XlaXTi₃O₁₂ (BLT).