Semiconductor device and method for fabricating the same using damascene process

• US 6,617,212 B2
• Filed: 06/29/2001
• Issued: 09/09/2003
• Est. Priority Date: 06/30/2000
• Status: Expired due to Fees

• Current Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Original Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Inventors: Park, Dea Gyu, Cho, Heung Jae
• Primary Examiner(s): Smith, Matthew
• Assistant Examiner(s): Luu, Chuong A
• Application Number:
  US09/893,650
• Publication Number:
  US 20020000623A1
• Time in Patent Office: 802 Days
• Field of Search: 438/183, 438/270, 438/289, 438/291, 438/290, 438/197, 438/259, 438/271, 438/589, 438/288, 438/330, 438/332
• US Class Current: 438/270
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/28123 Lithography-related aspects, e.g. sub-lithography lengths; Isolation-related aspects, e.g. to solve problems arising at the crossing with the side of the device isolation; Planarisation aspects
• CPC Class Codes: H01L 21/31616 Deposition of Al2O3
• CPC Class Codes: H01L 29/66545 using a dummy, i.e. replacement gate in a process wherein at least a part of the final gate is self aligned to the dummy gate

Abstract

A semiconductor device and a method for fabricating the semiconductor device using a damascene process are disclosed. The method includes forming an Al₂O₃ film over a dummy gate disposed over a semiconductor substrate. Next, the dummy gate and a portion of the Al₂O₃ film are removed to form a groove defined by remains of the Al₂O₃ film and the semiconductor substrate. Then, a subsequent film is deposited within the groove, and a gate material is formed over the second film to complete the semiconductor device.

Claims

1. A method for fabricating a semiconductor device using a damascene process, comprising the steps of:

forming a dummy gate electrode on a semiconductor substrate;

forming an Al₂O₃ film over the dummy gate electrode and the semiconductor substrate by depositing an AlON film over the substrate and

then thermally treating the AlON film to thereby form the Al₂O₃ film;

polishing and planarizing the Al₂O₃ film to expose the dummy gate electrode;

etching the dummy gate electrode to form a groove therein;

forming an insulating film on a surface of the groove; and

forming a gate electrode on the insulating film in the groove.

2. The method of claim 1, wherein the Al₂O₃ film has a thickness of 10 to 150 Å

.

3. The method of claim 1, wherein the Al₂O₃ film is deposited by an ALD or CVD process.

4. The method of claim 1, wherein the Al₂O₃ film has a thickness of 5 to 500 Å

and is subjected to an inert gas heat treatment at a temperature of 400 to 1,000°

C.

5. The method of claim 4, wherein the inert gas heat treatment uses a gas selected from one of O₂ and N₂O.

6. The method of claim 1, wherein the dummy gate electrode comprises a dummy gate insulating film and a dummy gate electrode silicon film.

7. A method for fabricating a semiconductor device using a damascene process, comprising the steps of:

forming a dummy gate on a semiconductor substrate, the dummy gate including a dummy gate insulating film and a dummy gate electrode;

forming an oxide film over the semiconductor substrate using an LDD oxidation process;

wet-etching the oxide film, wherein the dummy gate insulating film is etched to have a selected slope during wet-etching of the oxide film;

forming an Al₂O₃ film over the semiconductor substrate and the dummy gate;

forming source and drain regions in the semiconductor substrate;

activating the source and drain regions;

forming an interlayer insulating film over the substrate;

polishing the interlayer insulating film and the Al₂O₃ film using a Chemical Mechanical Polishing process to expose the dummy gate electrode;

etching the dummy gate electrode and the dummy gate insulating film in sequence to form a groove defining a gate electrode region;

forming a gate insulating film on a surface of the groove; and

forming a doped polysilicon film or a gate metal film on the gate insulating film in the groove.

8. The method of claim 7, wherein the dummy gate insulating film is deposited having a thickness of 10 to 150 Å

.

9. The method of claim 7, wherein the Al₂O₃ film is formed using an ALD or CVD process.

10. The method of claim 7, wherein the Al₂O₃ film has a thickness of 5 to 500 Å

and is subjected to an inert gas heat treatment at a temperature of 400 to 1,000°

C.

11. The method of claim 7, wherein the Al₂O₃ film is formed by depositing an AlON film over the substrate and then thermally treating the AlON film to thereby form the Al₂O₃ film.

12. A method of fabricating a semiconductor device using a damascene process, comprising the steps of:

forming a dummy gate on a semiconductor substrate, the dummy gate including a dummy gate insulating film and a dummy gate electrode;

forming an oxide film over the semiconductor substrate using an LDD oxidation process;

wet-etching the oxide film, wherein the dummy gate insulating film is etched to have a selected slope during wet-etching of the oxide film;

depositing an AlON over the semiconductor substrate;

heat-treating the semiconductor substrate to transform the AlON film into an Al₂O₃ film;

performing low concentration impurity implantation into the semiconductor substrate to form an LDD region in the substrate;

forming spacers on sidewalls of the dummy gate;

performing high concentration impurity implantation into the semiconductor substrate to form a source/drain region;

heat-treating the substrate to activate the implanted impurity ions;

forming an interlayer insulating film over the semiconductor substrate;

polishing the interlayer insulating film and the Al₂O₃ film using a Chemical Mechanical Polishing process to expose the dummy gate electrode;

etching the dummy gate electrode and the dummy gate insulating film in sequence to form a groove defining a gate electrode region;

forming a gate insulating film on a surface of the groove; and

forming a doped polysilicon film or a gate metal film on the gate insulating film in the groove, thereby forming a gate of the semiconductor device.

13. The method of claim 12, wherein the dummy gate insulating film is formed having a thickness of 10 to 150 Å

.

14. The method of claim 12, wherein the AlON film is deposited by an ALD or CVR process.

15. The method of claim 12, wherein the Al₂O₃ film has a thickness of 5 to 500 Å

and is subjected to an inert gas heat treatment at a temperature of 400 to 1,000°

C.