Atomic layer deposition of oxide film

• US 20040168627A1
• Filed: 02/27/2003
• Published: 09/02/2004
• Est. Priority Date: 02/27/2003
• Status: Abandoned Application

• Current Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Laboratories of America Incorporated (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Ono, Yoshi, Conley, John F. Jr., Solanki, Rajendra
• Application Number:
  US10/376,774
• Publication Number:
  US 20040168627A1
• Time in Patent Office: Days
• US Class Current: 117/89
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 25/14 Feed and outlet means for the gases; Modifying the flow of the reactive gases
• CPC Class Codes: C30B 29/16 Oxides

Abstract

An atomic layer deposition method to deposit a oxide thin film is provided. The method employs a nitrate ligand in a first hafnium precursor as an oxidizer for a second hafnium precursor to form the hafnium oxide. Using a hafnium nitrate precursor and a hafnium chloride precursor, the method is well suited for the deposition of a high k hafnium oxide dielectric for gate dielectric or capacitor dielectric applications on a hydrogen-terminated silicon surface.

Claims

1. A method for using a hafnium nitrate-containing precursor as an oxidizing agent for a hafnium-containing precursor in an atomic layer deposition process for the formation of a hafnium oxide film, the method comprising the steps of:

a. introducing a hafnium nitrate-containing precursor;

b. purging the hafnium nitrate-containing precursor;

c. introducing a hafnium-containing precursor; and

d. purging the hafnium-containing precursor.

2. The method of claim 1, wherein some, but not all, of the nitrate ligands of the hafnium nitrate-containing precursor are replaced with a substituent R, the substituent R being selected from a group consisting of hydrogen, oxygen, oxynitrates, hydroxyl, aromatic, amine, alkyl, silyl, alkoxide, diketone, and mixtures thereof.

3. The method of claim 1, wherein the hafnium-containing precursor is a non oxygen containing hafnium precursor.

4. The method of claim 1, wherein the hafnium-containing precursor is selected from a group consisting of hafnium alkyls, hafnium halides, hafnium diketonates, hafnium alkoxides, hafnium hydrides, hafnium silyls, hafnium amides, hafnium acetylacetonates, hafnium t-butoxides, hafnium ethoxides and mixtures and combinations thereof.

5. The method of claim 1, further comprising a step of heating the substrate to a temperature below 200°

C. before step a.

6. The method of claim 1, wherein the purging step is accomplished by flowing nitrogen or inert gas into the chamber.

7. The method of claim 1, wherein the purging step is accomplished by evacuating the chamber of all gases.

8. The method of claim 1, wherein the steps are repeated until a desired thickness is reached.

9. The method of claim 1, further comprising a post deposition anneal step after the desired thickness is reached.

10. A method for using a hafnium nitrate precursor as an oxidizing agent for a hafnium-containing precursor in an atomic layer deposition process for the formation of a hafnium oxide film on a semiconductor substrate, the method comprising the steps of:

a. providing a hydrogen-terminated silicon surface on the semiconductor substrate within an atomic layer deposition chamber;

b. introducing a hafnium nitrate precursor into the chamber;

c. purging the chamber;

d. introducing a hafnium-containing precursor into the chamber; and

e. purging the chamber.

11. The method of claim 10, wherein the hafnium nitrate precursor is an anhydrous hafnium nitrate precursor.

12. The method of claim 10, wherein the hafnium-containing precursor is a hafnium halide precursor.

13. The method of claim 10, wherein the hafnium-containing precursor is an organo metallic precursor selected from a group consisting of hafnium tert-butoxide, hafnium oxychloride, hafnium triflate.

14. The method of claim 10, further comprising a step of heating the substrate to a temperature below 200°

C. after step a and before step b.

15. The method of claim 10, wherein the chamber purging step is accomplished by flowing nitrogen or inert gas into the chamber.

16. The method of claim 10, wherein the chamber purging step is accomplished by evacuating the chamber of all gases.

17. The method of claim 10, wherein the steps b to e are repeated until a desired thickness is reached with the last step being step b or step c.

18. The method of claim 10, wherein the steps b to e are repeated until a desired thickness is reached with the last step being step d or step e.

19. The method of claim 18, further comprising a post deposition anneal step after the desired thickness is reached.

20. The method of claim 19, wherein the post deposition anneal time is between 10 sec to 5 minutes and the post deposition anneal temperature is between 400°

C. to 1000°

C.