Selective deposition method

• US 20080242097A1
• Filed: 03/28/2007
• Published: 10/02/2008
• Est. Priority Date: 03/28/2007
• Status: Abandoned Application

• Current Assignee: Qimonda AG (Infineon Technologies AG)
• Original Assignee: Qimonda AG (Infineon Technologies AG)
• Inventors: Jakschik, Stefan, Boescke, Tim, Hecht, Thomas, Saenger, Annette, Avellan, Alejandro, Patz, Matthias, Sundqvist, Jonas, Fachmann, Christian
• Application Number:
  US11/729,360
• Publication Number:
  US 20080242097A1
• Time in Patent Office: Days
• US Class Current: 438/703
• CPC Class Codes: C30B 25/04 Pattern deposit, e.g. by using masks
• CPC Class Codes: H01L 21/02148 the material containing hafnium, e.g. HfSiOx or HfSiON
• CPC Class Codes: H01L 21/02159 the material containing zirconium, e.g. ZrSiOx
• CPC Class Codes: H01L 21/02164 the material being a silicon oxide, e.g. SiO2
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• 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 21/02189 the material containing zirconium, e.g. ZrO2
• CPC Class Codes: H01L 21/0228 deposition by cyclic CVD, e.g. ALD, ALE, pulsed CVD
• CPC Class Codes: H01L 21/02304 formation of intermediate layers, e.g. buffer layers, layers to improve adhesion, lattice match or diffusion barriers
• CPC Class Codes: H01L 21/31604 Deposition from a gas or vapour H01L21/31691, H01L21/31695 take precedence
• CPC Class Codes: H01L 21/31612 on a silicon body
• 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 29/945 Trench capacitors

Abstract

The invention refers to a selective deposition method. A substrate comprising at least one structured surface is provided. The structured surface comprises a first area and a second area. The first area is selectively passivated regarding reactants of a first deposition technique and the second area is activated regarding the reactants the first deposition technique. A passivation layer on the second area is deposited via the first deposition technique. The passivation layer is inert regarding a precursors selected from a group of oxidizing reactants. A layer is deposited in the second area using a second atomic layer deposition technique as second deposition technique using the precursors selected form the group of oxidizing reactants.

Claims

1. A selective deposition method comprising the following steps of:

(a) providing a substrate comprising at least one structured surface, the structured surface comprising a first area and a second area;

(b) selectively passivating the first area regarding reactants of a first deposition technique and activating the second area regarding the reactants of the first deposition technique;

(c) depositing a passivation layer on the second area via the first deposition technique, the passivation layer being inert regarding a precursor selected from a group of oxidizing reactants;

(d) depositing a layer in the second area using a second atomic layer deposition technique as a second deposition technique using the precursor selected form the group of oxidizing reactants.

2. The selective deposition method according to claim 1, wherein first deposition technique is a first atomic layer deposition technique and the reactants being precursors of the first atomic layer deposition technique.

3. The selective deposition method according to claim 1, wherein the first deposition technique is one of a gas phase deposition technique providing the reactant, a spin-on technique providing the reactant, and a dip-in technique using a watery solution of the reactant.

4. The selective deposition method according to claim 1,

wherein the first area is passivated by removing at least one of hydroxyl functional groups and amine functional groups from the first area and

wherein the second area is activated by forming the at least one of hydroxyl functional groups and amine functional groups on the second area, which are removed in the first area.

5. The selective deposition method according to claim 1,

wherein the selective passivating of the first area and the selective activating of the second area comprises the steps of:

(a) selectively forming a layer of at least one of a silicon oxide layer and a silicon nitride layer on the second area;

(b) selecting an etchant of a group of etchants etching silicon oxide when the layer is formed to comprise silicon oxide and is chosen of a group of etchants etching silicon nitride when the layer is formed to comprise silicon nitride;

(c) applying the etchant to the first area and to the second area for a duration such that parasitic silicon oxide and parasitic silicon nitride are removed in the first area and the formed silicon oxide and the formed silicon nitride remains in the second area.

6. The selective deposition method according to claim 5, wherein the first area is masked for selectively forming the layer of at least one of a silicon oxide layer and a silicon nitride layer on the second area.

7. The selective deposition method according to claim 1,

wherein the selective passivating of the first area and the selective activating of the second area comprises the steps of:

(a) selectively forming a layer of a silicon oxide layer on the second area; and

(b) etching the first area and the second area until parasitic silicon hydroxyl is removed in the first area using an etchant being selected of hydrofluoric acid or a mixture comprising hydrofluoric acid and ammonia.

8. The selective deposition method according to claim 2,

wherein the selective passivating of the first area and the selective activating of the second area comprises the steps of:

(a) selectively forming a layer of at least one of a aluminium oxide and a aluminium nitride on the second area via a non-conformal atomic layer deposition technique; and

(b) applying an etchant to the first area and the second area until parasitic silicon hydroxyl is removed in the first area, the etchant being selected of a species the layer is inert against.

9. The selective deposition method according to claim 8, wherein the etchant is chosen of hydrofluoric acid or a mixture comprising hydrofluoric acid and ammonia.

10. The selective deposition method according to claim 1, wherein the group of oxidizing reactants is selected of at least one of water, ozone, diatomic oxygen, ammonia and hydrazine.

11. The selective deposition method according to claim 1,

wherein the first atomic layer deposition technique employs a precursor chosen from a group of compounds of the constitutional formulas R¹Si Cl₃, R²AlCl₂, R³COR⁴, R⁵SO₂R⁶, and R⁷C_nF_xH_2n+1−

x, wherein R¹, R², R³, R⁴, R⁵, R⁶, and R⁷ are independently selected of alkyl functional groups.

12. The selective deposition method according to claim 11, wherein R¹, R², R⁴, and R⁵ are alkyl functional groups comprising four to twenty carbon atoms.

13. The selective deposition method according to claim 1,

wherein the first atomic layer deposition technique employs a precursor chosen from a group of hexamethyldisilizane (HN[Si(CH₃)₃]₂), decyltrichlorsilane (SiCl₃C₁₀H₂₁) and, octadecyltrichlorsilane (SiCl₃C₁₈H₃₇).

14. The selective deposition method according to claim 1, wherein the substrate comprises a trench, the at least one structured surface is provided as a side wall of a trench and the first area is closer to a bottom of the trench than the second area.

15. The selective deposition method according to claim 1, wherein the substrate comprises a bottom surface and at least one structure surface having a first area and a second area, the first area being closer to the bottom surface than the second area.

20. The selective deposition method according to claim 6, the structured surface being a trench in the substrate, the first area being a bottom area of the trench, wherein the first area is masked by filling the bottom area of the trench.

16. A selective deposition method comprising the following steps of:

(a) providing a silicon substrate comprising a bottom surface and at least one structured surface, the structured surface comprising a first area and a second area, the first area being closer to the bottom surface than the second area;

(b) selectively depositing at least one of silicon oxide and aluminium oxide on the second area;

(c) etching the first area and the second area until parasitic silicon hydroxyl is removed in the first area;

(d) depositing a passivation layer on the second area being inert against at least one of water and ozone via a first atomic layer deposition technique, the first atomic layer deposition technique using at least one of hexamethyldisilizane (HN[Si(CH₃)₃]₂), decyltrichlorsilane (SiCl₃C₁₀H₂₁), and octadecyltrichlorsilane (SiCl₃C₁₈H₃₇) as precursor;

(e) activating the passivated first area using at least one of water and ozone for forming silicon hydroxyl in the second area;

(f) depositing a transition metal oxide via a second atomic layer deposition technique using one precursor selected from water and ozone and an other precursor chosen as compound of one of the constitutional formulas M(R¹Cp)₂ (R²)₂ and MR³R⁴R⁵R⁶, wherein M is one of hafnium and zirconium, Cp is cyclopentadienyl, R¹ is independently selected of hydrogen, and alkyl, R² is independently selected of hydrogen, methyl, ethyl, alkyl, alkoxy, and halogene; and

R³, R⁴, R⁵, and R⁶ are independently selected of hydrogen and alkyl amines.

21. The selective deposition method according to claim 16, wherein a dopant is applied along to depositing the transition metal oxide, the dopant being chosen of at least one of silicon, aluminium, rare earth metal, titanium, hafnium, tantalum, barium, scandium, yttrium, lanthanum, niobium, bismuth, calcium and cerium.

17. A structured semiconductor device, comprising:

a substrate comprising at least one structured surface, the structured surface comprising a first area and a second area, and

a layer comprising at least one of a transition metal oxide and a transition metal nitride on the second area deposited via an atomic layer deposition technique, the second area being substantially free of the at least one of the transition metal oxide and the transition metal nitride.

18. An integrated electronic circuit, comprising:

a structured semiconductor substrate in which a trench is formed, the trench comprising a collar region, and a bottle region;

a dielectric layer of at least one of a transition metal oxide and a transition metal nitride formed on the second surface deposited via an atomic layer deposition technique, the bottle region being substantially free of the at least one of the transition metal oxide and the transition metal nitride.

19. A memory device comprising the integrated electronic circuit according to claim 18.