Gas supplying method and semiconductor manufacturing apparatus

• US 10,410,840 B2
• Filed: 02/05/2015
• Issued: 09/10/2019
• Est. Priority Date: 02/12/2014
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Mizutani, Tomoyuki, Tsujimoto, Hiroshi
• Primary Examiner(s): Lund, Jeffrie R
• Assistant Examiner(s): Antolin, Stanislav
• Application Number:
  US14/614,900
• Publication Number:
  US 20150228460A1
• Time in Patent Office: 1,678 Days
• CPC Class Codes: C23C 14/54 Controlling or regulating the coating process
• CPC Class Codes: C23C 16/45523 Pulsed gas flow or change of composition over time
• CPC Class Codes: H01J 37/3244 Gas supply means
• CPC Class Codes: H01J 37/32449 Gas control, e.g. control of the gas flow
• CPC Class Codes: H01L 21/31138 by dry-etching
• CPC Class Codes: H01L 21/67109 mainly by convection
• CPC Class Codes: H01L 21/67253 Process monitoring, e.g. flow or thickness monitoring
• CPC Class Codes: Y10T 137/0324 With control of flow by a condition or characteristic of a fluid

Abstract

A gas supplying method of supplying a process gas containing a gas of at least one gaseous species into a process space in a semiconductor manufacturing apparatus includes supplying the process gas by controlling a flow rate value of the gas to be a first value during a first period; supplying the process gas by controlling the flow rate value of the gas to be a second value smaller than the first value during a second period; supplying the process gas by controlling the flow rate value of the gas to be a third value greater than the first value during a third period; and supplying the process gas by controlling the flow rate value of the gas to be a fourth value smaller than the second value during a fourth period, wherein these steps are periodically repeated in a predetermined order.

Claims

1. A gas supplying method of supplying a process gas containing a gas of at least one gaseous species into a process space in a semiconductor manufacturing apparatus, the gas supplying method comprising:

a first step of supplying the process gas containing the gas by controlling a flow rate value of the gas to be a first flow rate value during a first period;

a second step of supplying the process gas containing the gas by controlling the flow rate value of the gas to be a second flow rate value smaller than the first flow rate value during a second period;

a third step of supplying the process gas containing the gas by controlling the flow rate value of the gas to be a third flow rate value greater than the first flow rate value during a third period; and

a fourth step of supplying the process gas containing the gas by controlling the flow rate value of the gas to be a fourth flow rate value smaller than the second flow rate value during a fourth period,

wherein one cycle, which has only four periods of the first period, the second period, the third period, and the fourth period corresponding to the first step, the second step, the third step, and the fourth step in a predetermined order, is periodically repeated, and

wherein the predetermined order in the one cycle is that

the fourth step is immediately before the second step,

the third step is immediately before the first step, and

the second step is before the first step.

2. The gas supplying method according to claim 1,

wherein the process space is a plasma generation space where plasma is generated from the process gas,

wherein a data group indicative of a correlations between the flow rate of the gas and an emission intensity of the plasma generated in the plasma generation space is acquired by detecting the emission intensity relative to the flow rate of the gas and stored in a memory unit comprising a non-transitory computer readable medium,

wherein the third flow rate value and the fourth flow rate value are set by converting a detection value of the emission intensity of the plasma generated in the plasma generation space to the flow rate value of the gas based on the correlations between the flow rate of the gas and the emission intensity of the plasma of the gas.

3. The gas supplying method according to claim 2,

wherein the third flow rate value is appropriately determined based on a comparative result obtained by comparing the converted flow rate value and the first flow rate value,

wherein the fourth flow rate value is appropriately determined based on a comparative result obtained by comparing the converted flow rate value and the second flow rate value.

4. The gas supplying method according to claim 1,

wherein the first flow rate value, the second flow rate value, the third flow rate value, and the fourth flow rate value are positive values.

5. The gas supplying method according to claim 1,

wherein the flow rate value of the gas of the at least one gaseous species is controlled for each of the first period, the second period, the third period, and the fourth period.

6. The gas supplying method according to claim 1,

wherein the fourth period is longer than the third period.