Amorphous high-k thin film and manufacturing method thereof

• US 7,379,322 B2
• Filed: 02/15/2006
• Issued: 05/27/2008
• Est. Priority Date: 02/15/2005
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Cho, Young-jin, Min, Yo-sep
• Primary Examiner(s): Purvis; Sue A.
• Assistant Examiner(s): Rodela; Eduardo A.
• Application Number:
  US11/354,013
• Publication Number:
  US 20060180838A1
• Time in Patent Office: 832 Days
• Field of Search: 365/145
• US Class Current: 365/145
• CPC Class Codes: C23C 16/40 Oxides
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: H01L 21/02175 characterised by the metal H01L21/02197 takes precedence
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02186 the material containing titanium, e.g. TiO2
• CPC Class Codes: H01L 21/02194 the material containing more than one metal element
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/3141 Deposition using atomic layer deposition techniques [ALD]
• CPC Class Codes: H01L 21/31616 Deposition of Al2O3
• CPC Class Codes: H01L 21/31691 with perovskite structure
• CPC Class Codes: H01L 28/55 with a dielectric comprising a perovskite structure material

Abstract

An amorphous high-k thin film for a semiconductor device and a manufacturing method thereof are provided. The amorphous high-k thin film includes Bi, Ti, Al, and O. Since a BTAO based amorphous dielectric thin film is used as a dielectric material of a DRAM capacitor, a dielectric constant is more than 25, and an increase of a leakage current caused in reducing a physical thickness of the dielectric thin film can be prevented. Accordingly, it is very useful for the integration of the semiconductor device.

Claims

1. A high-k thin film for a memory device consisting of an amorphous film of Bi, Ti, Al, and O.

2. The amorphous high-k thin film of claim 1, wherein Bi and Ti are present in a similar fraction to each other.

3. The amorphous high-k thin film of claim 1, wherein the fraction of Al is below 50%.

4. The amorphous high-k thin film of claim 1, wherein the thin film has a dielectric constant of about 25.

5. An amorphous high-k thin film for a memory device, wherein the amorphous high-k film is formed of Bi_1-x-yTi_yAl_yO_z(0.2<

×

<

0.5, 0<

y<

0.5, 1.5<

Z<

3).

6. A method of manufacturing an amorphous high-k thin film for a semiconductor device, the semiconductor device including a bottom structure, a dielectric thin film, and a top electrode, the method comprising:

forming the amorphous high-k film including Bi, Ti, Al, and O on the bottom structure, wherein the amorphous high-k thin film is formed of Bi_1-x-yTi_yAl_yO_z(0.2<

×

<

0.5, 0<

y<

0.5, 1.5<

Z<

3).

7. The method of claim 6, wherein the amorphous high-k thin film is formed by an atomic layer deposition.

8. The method of claim 7, wherein when forming of the amorphous high-k thin film, single layers of Bi, Ti and Al are formed as precursors on the bottom structure and at least one of O₃ and H₂O is used as a reaction gas.

9. The method of claim 7, wherein the forming of the amorphous high-k thin film comprises:

forming Bi and Ti thin films as Bi and Ti precursors on the bottom structure, and performing oxidation to form Bi and Ti oxide film; and

forming an Al thin film as an Al precursor on the Bi and Ti oxide layers, and performing oxidation to form an Al oxide film.