Method for depositing a nanolaminate film by atomic layer deposition

• US 6,930,059 B2
• Filed: 02/27/2003
• Issued: 08/16/2005
• Est. Priority Date: 02/27/2003
• Status: Active Grant

• 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
• Primary Examiner(s): Fourson, George
• Assistant Examiner(s): Toledo, Fernando L.
• Application Number:
  US10/376,794
• Publication Number:
  US 20040171280A1
• Time in Patent Office: 901 Days
• Field of Search: 117/89, 438/785, 427/97.1, 427/126.4, 427/126.6
• US Class Current: 438/785
• CPC Class Codes: C23C 16/40 Oxides
• CPC Class Codes: C23C 16/45529 specially adapted for making a layer stack of alternating different compositions or gradient compositions
• CPC Class Codes: C23C 16/45531 specially adapted for making ternary or higher compositions
• CPC Class Codes: C23C 16/56 After-treatment
• CPC Class Codes: H01L 21/02178 the material containing aluminium, e.g. Al2O3
• CPC Class Codes: H01L 21/02181 the material containing hafnium, e.g. HfO2
• 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 21/02205 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 21/28185 with a treatment, e.g. annealing, after the formation of the gate insulator and before the formation of the definitive gate conductor
• CPC Class Codes: H01L 21/28194 by deposition, e.g. evaporation, ALD, CVD, sputtering, laser deposition H01L21/28202 takes precedence
• CPC Class Codes: H01L 21/28202 in a nitrogen-containing ambient, e.g. nitride deposition, growth, oxynitridation, NH3 nitridation, N2O oxidation, thermal nitridation, RTN, plasma nitridation, RPN
• CPC Class Codes: H01L 21/3142 of nano-laminates, e.g. alternating layers of Al203-Hf02
• CPC Class Codes: H01L 21/31616 Deposition of Al2O3
• CPC Class Codes: H01L 21/31645 Deposition of Hafnium oxides, e.g. HfO2
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/513 the variation being perpendicular to the channel plane
• CPC Class Codes: H01L 29/517 the insulating material comprising a metallic compound, e.g. metal oxide, metal silicate H01L29/518 takes precedence
• CPC Class Codes: H01L 29/518 the insulating material containing nitrogen, e.g. nitride, oxynitride, nitrogen-doped material
• CPC Class Codes: H01L 29/66583 with initial gate mask or masking layer complementary to the prospective gate location, e.g. with dummy source and drain contacts

Abstract

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

Claims

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

a. introducing a first metal nitrate-containing precursor;

b. forming a first metal nitrate;

c. purging the first metal nitrate-containing precursor;

d. introducing a second metal-containing precursor;

e. oxidizing the second metal-containing precursor in response to the first metal nitrate; and

f. purging the second metal-containing precursor.

2. The method of claim 1, wherein the metals are selected from a group consisting of Cu, Zn, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Co, Ni, Al, Ga, In, Ge, Sn, La, Ce, Nd, Sm, Gd.

3. The method of claim 1, wherein some, but not all, of the nitrate ligands of the first metal 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.

4. The method of claim 1, wherein the second metal-containing precursor is a non oxygen containing precursor.

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

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

a. introducing a hafnium nitrate-containing precursor;

b. forming a hafnium nitrate film;

c. purging the hafnium nitrate-containing precursor;

d. introducing a metal-containing precursor;

e. oxidizing the metal-containing precursor in response to the hafnium nitrate film; and

f. purging the metal-containing precursor.

7. The method of claim 6, 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.

8. The method of claim 6, wherein the metal-containing precursor is a non oxygen containing precursor.

9. The method of claim 6, wherein the metal-containing precursor is selected from a group consisting of metal alkyls, metal halides, metal diketonates, metal alkoxides, metal hydrides, metal silyls, metal amides, metal acetylacetonates, metal t-butoxides, metal ethoxides and mixtures and combinations thereof.