Thick tungsten hardmask films deposition on high compressive/tensile bow wafers

• US 10,504,727 B2
• Filed: 09/05/2017
• Issued: 12/10/2019
• Est. Priority Date: 09/13/2016
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Wang, Jiarui, Kulshreshtha, Prashant Kumar, Venkatasubramanian, Eswaranand, Roy, Susmit Singha, Lee, Kwangduk Douglas
• Primary Examiner(s): Gumedzoe, Peniel M
• Assistant Examiner(s): Johnson, Christopher A
• Application Number:
  US15/695,180
• Publication Number:
  US 20180076032A1
• Time in Patent Office: 826 Days
• CPC Class Codes: C23C 16/0272 Deposition of sub-layers, e.g. to promote the adhesion of the main coating
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/342 Boron nitride
• CPC Class Codes: C23C 16/345 Silicon nitride
• CPC Class Codes: C23C 16/401 containing silicon
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: C23C 16/50 using electric discharges generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34
• CPC Class Codes: C23C 16/505 using radio frequency discharges
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence
• CPC Class Codes: H01L 21/02112 characterised by the material of the layer
• 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 21/02175 characterised by the metal H01L21/02197 takes precedence
• CPC Class Codes: H01L 21/02205 the layer being characterised by the precursor material for deposition
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• 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 21/0332 characterised by their composition, e.g. multilayer masks, materials
• CPC Class Codes: H01L 21/0337 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
• CPC Class Codes: H01L 21/31144 using masks
• CPC Class Codes: H01L 21/67103 mainly by conduction
• CPC Class Codes: H01L 21/6831 : using electrostatic chucks
• CPC Class Codes: H10B 41/27 : the channels comprising vertical portions, e.g. U-shaped channels
• CPC Class Codes: H10B 41/50 : characterised by the boundary region between the core region and the peripheral circuit region
• CPC Class Codes: H10B 43/27 : the channels comprising vertical portions, e.g. U-shaped channels
• CPC Class Codes: H10B 43/50 : characterised by the boundary region between the core and peripheral circuit regions

Abstract

Implementations of the present disclosure generally relate to the fabrication of integrated circuits. More particularly, the implementations described herein provide techniques for deposition of thick hardmask films on a substrate. In one implementation, a method of forming a hardmask layer on a substrate is provided. The method comprises applying a chucking voltage to a substrate positioned on an electrostatic chuck in a processing chamber, forming a seed layer comprising boron on a film stack disposed on a substrate by supplying a seed layer gas mixture in the processing chamber while maintaining the chucking voltage, forming a transition layer comprising boron and tungsten on the seed layer by supplying a transition layer gas mixture in the processing chamber and forming a bulk hardmask layer on the transition layer by supplying a main deposition gas mixture in the processing chamber.

Claims

1. A method of forming a hardmask layer on a substrate comprising:

applying a chucking voltage to a substrate positioned on an electrostatic chuck in a processing chamber;

forming a seed layer comprising boron on a film stack disposed on the substrate by supplying a seed layer gas mixture in the processing chamber while maintaining the chucking voltage, wherein the seed layer gas mixture comprises at least a boron-based precursor gas and a nitrogen-based precursor gas;

forming a transition layer comprising boron and tungsten on the seed layer by supplying a transition layer gas mixture in the processing chamber, wherein supplying the transition layer gas mixture comprises;

ramping down a gas flow rate of the boron-based precursor gas while maintaining a steady gas flow rate of the nitrogen-based precursor gas; and

supplying a tungsten-based precursor gas; and

forming a bulk hardmask layer on the transition layer by supplying a main deposition gas mixture in the processing chamber.

2. The method of claim 1, wherein the chucking voltage is between about 10 volts and about 3,000 volts.

3. The method of claim 2, wherein the chucking voltage is between about 200 volts and about 1,000 volts.

4. The method of claim 3, wherein the seed layer comprising boron is formed in the presence of a plasma.

5. The method of claim 4, wherein the plasma is formed in-situ.

6. The method of claim 5, wherein the plasma is formed using mixed frequency RF.

7. The method of claim 1, wherein forming the seed layer is performed without a shadow ring encircling a perimeter of the substrate.

8. The method of claim 1, wherein the film stack comprises repeating layers of a first dielectric layer and a second dielectric layer.

9. The method of claim 8, wherein the first dielectric layer is a silicon oxide layer and the second dielectric layer is a silicon nitride layer.

10. The method of claim 1, wherein a gas flow rate of the tungsten-based precursor gas is ramped up at a ramp up rate in the transition layer gas mixture while the gas flow rate of the boron-based precursor gas is ramped down.

11. The method of claim 10, wherein the tungsten-based precursor gas is ramped up at a rate similar to the ramp down rate of the boron-based precursor gas.

12. The method of claim 11, wherein forming the bulk hardmask layer further comprises:

steadily supplying the tungsten-based precursor gas and the nitrogen-based precursor gas in the processing chamber.

13. The method of claim 1, wherein the boron-based precursor gas is B₂H₆ and the nitrogen-based precursor gas is at least one of N₂ and NH₃.

20. The method of claim 13, wherein the tungsten-based precursor gas is WF₆.

14. A method of forming a hardmask layer on a substrate comprising:

applying a chucking voltage to a substrate positioned on an electrostatic chuck in a processing chamber;

forming a seed layer comprising boron on a film stack disposed on the substrate by;

supplying a seed layer gas mixture in the processing chamber while maintaining the chucking voltage, wherein the seed layer gas mixture comprises at least a boron-based precursor gas and a nitrogen-based precursor gas; and

steadily supplying the nitrogen-based precursor gas and varying a flow of the boron-based precursor gas in the processing chamber to form the seed layer;

forming a transition layer comprising boron and tungsten on the seed layer by supplying a transition layer gas mixture in the processing chamber, wherein supplying the transition layer gas mixture comprises;

ramping down a gas flow rate of the boron-based precursor gas while maintaining a steady gas flow rate of the nitrogen-based precursor gas; and

supplying a tungsten-based precursor gas; and

forming a bulk hardmask layer on the transition layer by supplying a main deposition gas mixture in the processing chamber.

15. The method of claim 14, wherein forming the bulk hardmask layer further comprises:

steadily supplying the tungsten-based precursor gas and a carbon-based precursor gas in the processing chamber.

16. The method of claim 15, wherein forming the seed layer further comprises supplying a hydrogen-based precursor gas into the processing chamber.

17. The method of claim 16, wherein the film stack is used to form stair-like structures to form three dimension NAND memory devices.

18. The method of claim 14, wherein the film stack comprises repeating layers of a silicon oxide layer and a silicon nitride layer.

19. A method of forming a hardmask layer on a substrate comprising:

applying a chucking voltage to a substrate positioned on an electrostatic chuck in a processing chamber;

forming a boron nitride layer on a film stack disposed on the substrate by supplying a seed layer gas mixture in the processing chamber while maintaining the chucking voltage, wherein the seed layer gas mixture comprises at least a boron-based precursor gas and a nitrogen-based precursor gas;

forming a boron tungsten nitride layer on the boron nitride layer by supplying a transition layer gas mixture in the processing chamber, wherein supplying the transition layer gas mixture comprises;

ramping down a gas flow rate of the boron-based precursor gas while maintaining a steady gas flow rate of the nitrogen-based precursor gas; and

supplying a tungsten-based precursor gas; and

forming a tungsten nitride layer on the boron nitride layer by supplying a main deposition gas mixture in the processing chamber.