Rotating semi-batch ALD device

• US 10,480,073 B2
• Filed: 08/21/2015
• Issued: 11/19/2019
• Est. Priority Date: 04/07/2013
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Shigemi Murakawa
• Inventors: Murakawa, Shigemi
• Primary Examiner(s): Bennett, Charlee J C
• Application Number:
  US14/831,884
• Publication Number:
  US 20150361553A1
• Time in Patent Office: 1,551 Days
• Field of Search: 1563451-34555
• CPC Class Codes: C23C 16/4412 Details relating to the exhausts, e.g. pumps, filters, scrubbers, particle traps
• CPC Class Codes: C23C 16/45551 for relative movement of the substrate and the gas injectors or half-reaction reactor compartments
• CPC Class Codes: C23C 16/45561 Gas plumbing upstream of the reaction chamber
• CPC Class Codes: C23C 16/45565 Shower nozzles
• CPC Class Codes: C23C 16/52 Controlling or regulating the coating process C23C16/45557, C23C16/279 take precedence

Abstract

The present invention provides a rotating semi-batch ALD device and process which ensure high productivity, minimal particle formation, low gas consumption and high coverage during the production of semiconductors, liquid crystals, LEDs and/or solar cells. The rotating semi-batch ALD device and ALD process are characterized in that: a reaction gas supply means is configured from a shower plate for evenly discharging gas, a cavity for allowing gas to flow down gradually, and a partition wall surrounding the shower plate and the cavity; and a purge gas supply means is configured from a shower plate that causes gas to flow evenly at a high flow velocity in the transverse direction in the narrow gap between the purge gas supply means and substrates being treated.

Claims

1. A rotating semi-batch ALD device, comprising:

a vacuum container,

a rotating susceptor,

a plurality of substrates being processed disposed on the susceptor,

a substrate heating heater,

a plurality of substantially sector-shaped reaction gas supply means disposed in an upper portion of the vacuum container,

a plurality of separate purge gas supply means disposed between the plurality of substantially sector-shaped reaction gas supply means, and

a vacuum evacuation means provided as an independent separate system for each reaction gas,

wherein

the rotating semi-batch ALD device repeatedly exposes the substrates to the reaction gas sequentially by rotating the susceptor to perform an ALD deposition,

an entire circumference of each reaction gas supply means is surrounded by a different one of a plurality of first vacuum evacuation grooves as first parts of the vacuum evacuation means, and

an entire circumference of each of the plurality of separate purge gas supply means is surrounded by a different one of a plurality of separate second vacuum evacuation grooves as second parts of the vacuum evacuation means.

2. The rotating semi-batch ALD device according to claim 1, wherein another purge gas supply means is disposed circularly in a central portion of the vacuum container, and a circumference of the another purge gas supply means is surrounded by a third vacuum evacuation groove as a third part of the vacuum evacuation means.

3. The rotating semi-batch ALD device according to claim 1,

wherein

at least one of the substantially sector-shaped reaction gas supply means comprises a porous shower plate, a cavity allowing the gas to flow down under the porous shower plate, and a partition wall surrounding the cavity, wherein the partition wall extends down to lower than a bottom surface of the porous shower plate to define the cavity,

the purge gas supply means comprises a narrow-gapped shower plate, and

a first gap between gas ejection holes of the narrow-gapped shower plate of the purge gas supply means and a top surface of the rotating susceptor is narrower than a second gap between gas ejection holes of the porous shower plate of the at least one reaction gas supply means and the top surface of the rotating susceptor, and no cavity is formed under the narrow-gapped shower plate of the purge gas supply means.

4. The rotating semi-batch ALD device according to claim 3, wherein a gas molecule excitation means is disposed in the cavity, wherein the cavity is disposed in the reaction gas supply means containing no metal.

5. The rotating semi-batch ALD device according to claim 4, wherein a means that introduces an etching gas for removing a deposition material into the gas molecule excitation means is disposed for etching the deposition material deposited on the substrates being processed and the susceptor or in the vacuum container.

6. The rotating semi-batch ALD device according to claim 3, wherein a pitch of arrangement of gas ejection holes of the shower plates for the reaction gas and purge gas is set to be 10 mm or less.

7. The rotating semi-batch ALD device according to claim 3, wherein an edge of the shower plate disposed in the reaction gas supply means has a shape with a curvature to prevent stagnation of the reaction gas at the edge.

8. The rotating semi-batch ALD device according to claim 3, wherein a height of the cavity disposed in the reaction gas supply means is set to be 5 cm or less.

9. The rotating semi-batch ALD device according to claim 3, wherein different ones of the reaction gas supply means are separated by a diameter of the substrates being processed or more such that any two of the reaction gas supply means do not come above the same substrate.

10. The rotating semi-batch ALD device according to claim 3, wherein a relative position relationship between the substrates being processed and a gas supply means at a time of starting and cutting off supply of each reaction gas is controlled to apply an ALD process on all the substrates being processed for the same number of cycles.

11. The rotating semi-batch ALD device according to claim 10, wherein a rotation speed of the susceptor at the time of starting and cutting off supply of each reaction gas is varied and controlled according to the relative position relationship between the substrate and the gas supply unit such that all the substrates being processed are in contact with the reaction gas supply means for the same exposure time.

12. The rotating semi-batch ALD device according to claim 10, wherein a pretreatment process is provided before the ALD process starts, and the relative position relationship between the substrates being processed and the gas supply means at the time of starting and cutting off supply of a pretreatment gas is controlled such that the pretreatment is applied to all the substrates being processed for substantially the same time.

13. The rotating semi-batch ALD device according to claim 3, wherein an ALD saturation reaction time, being a minimum time required for covering all adsorption sites on a surface of the substrate with a reaction gas precursor, is calculated according to a maximum aspect ratio of a pattern formed on the surface of the substrates being processed, and a substrate rotation speed is controlled such that the surface of the substrate is exposed longer than the ALD saturation reaction time, wherein the maximum aspect ratio is a ratio of a depth to a width of a hole or a trench.

14. The rotating semi-batch ALD device according to claim 13, wherein the aspect ratio at any time during the deposition and the ALD saturation reaction time corresponding to the aspect ratio are calculated and the substrate rotation speed is controlled in real time such that the surface of the substrates being processed is constantly exposed longer than the saturation reaction time.

15. The rotating semi-batch ALD device according to claim 14, wherein the ALD saturation reaction time is calculated and approximated by a linear function or a quadratic function of the maximum aspect ratio of the surface shape of the substrates being processed, and the substrate rotation speed is controlled such that the surface of the substrate is exposed longer than the calculated ALD saturation reaction time.

16. The rotating semi-batch ALD device according to claim 13, wherein the ALD saturation reaction time is calculated and approximated by a linear function or a quadratic function of the maximum aspect ratio of a surface shape of the substrates being processed, and the substrate rotation speed is controlled such that the surface of the substrate is exposed longer than the calculated ALD saturation reaction time.

17. The rotating semi-batch ALD device according to claim 16, wherein the quadratic function representing the ALD saturation reaction time is approximated by t_s0(1+γ

α

²), wherein the aspect ratio is represented by α and

t_s0 and γ

are set to be constant.

18. The rotating semi-batch ALD device according to claim 16, wherein a saturation time t_s1 of an aspect ratio α

₁ of a point at a process pressure P₁ and a temperature T₁ is measured, a saturation time t_s of the aspect ratio α

at random temperature T and pressure P is calculated by t_s=t_s1(α

/α

₁)²(P₁/P)(T₁/T)^0.5, and a rotation speed of the susceptor is adjusted to maintain an obtained saturation reaction time.

19. The rotating semi-batch ALD device according to claim 3, wherein the plurality of substantially sector-shaped reaction gas supply means comprise metal-containing reaction gas supply means and non-metal reaction gas supply means.