Semiconductor manufacturing apparatus and semiconductor manufacturing method

• US 9,899,278 B2
• Filed: 07/07/2015
• Issued: 02/20/2018
• Est. Priority Date: 02/06/2015
• Status: Active Grant

• Current Assignee: Kioxia Corporation
• Original Assignee: Toshiba Memory Corporation (Kioxia Corporation)
• Inventors: Ishikawa, Masao
• Primary Examiner(s): Tran, Binh X
• Application Number:
  US14/793,047
• Publication Number:
  US 20160233135A1
• Time in Patent Office: 959 Days
• Field of Search: 216 59, 216 60, 216 13
• CPC Class Codes: H01J 37/32963 End-point detection
• CPC Class Codes: H01J 37/32972 Spectral analysis
• CPC Class Codes: H01L 21/30604 Chemical etching
• CPC Class Codes: H01L 21/30655 comprising alternated and repeated etching and passivation steps, e.g. Bosch process
• CPC Class Codes: H01L 21/308 using masks H01L21/3063, H01L21/3065 take precedence
• CPC Class Codes: H01L 21/31138 by dry-etching
• CPC Class Codes: H01L 22/26 Acting in response to an ongoing measurement without interruption of processing, e.g. endpoint detection, in-situ thickness measurement endpoint detection arrangements in CMP apparatus B24B37/013, in discharge apparatus H01J37/32

Abstract

In one embodiment, a semiconductor manufacturing apparatus includes an extraction module configured to extract, in cycle etching that repeats first processes of etching a workpiece layer and second processes of performing different processing from the first processes for plural cycles, light emission intensities in the first processes for individual cycles. The apparatus further includes a detection module configured to detect an etching end point of the workpiece layer in the cycle etching, based on the light emission intensities of the plural cycles.

Claims

1. A semiconductor manufacturing method comprising:

extracting, in cycle etching that repeats first processes of etching a workpiece layer and second processes of performing different processing from the first processes for plural cycles, light emission intensities in the first processes for individual cycles; and

detecting an etching end point of the workpiece layer in the cycle etching, based on the light emission intensities of the plural cycles, comprising,

calculating decrease amounts of the light emission intensities for second to Nth cycles relative to the light emission intensity for a first cycle, where N is an integer of three or more, and

determining that the cycle etching reaches the etching end point at the Nth cycle when the decrease amount of the light intensity for the (N−

1)th cycle does not reach a threshold and the decease amount of the light intensity for the Nth cycle reaches the threshold.

2. The method of claim 1, wherein the etching end point is detected based on peak values of the light emission intensities for the individual cycles.

3. The method of claim 1, wherein the etching end point is detected based on average values of the light emission intensities for the individual cycles.

4. The method of claim 1, wherein

the first process of a Kth cycle forms a Kth concave portion in the workpiece layer by lowering a bottom face of a (K−

1)th concave portion that is formed in the workpiece layer in the first process of the (K−

1)th cycles, where K is an integer of two or more, and

the second process of the (K−

1)th cycle forms a (K−

1)th film on a side face of the (K−

1)th concave portion, the (K−

1)th film being used as a mask for an etching to lower the bottom face of the (K−

1)th concave portion in the first process of the Kth cycle.

5. The method of claim 1, further comprising displaying values obtained from the light emission intensities on a screen.

6. The method of claim 1, wherein a second process includes a process of forming a film on the workpiece layer.

7. The method of claim 6, wherein a first process includes a process of etching the workpiece layer by using the film as a mask.

8. The method of claim 6, wherein the second process further includes a breakthrough process of the film.