GAS SUPPLY SYSTEM, SUBSTRATE PROCESSING APPARATUS AND GAS SUPPLY METHOD

Abstract

A gas supply system for supplying a gas into a processing chamber for processing a substrate to be processed includes: a processing gas supply unit; a processing gas supply line; a first and a second branch line; a branch flow control unit; an additional gas supply unit; an additional gas supply line; and a control unit. The control unit performs, before processing the substrate to be processed, a processing gas supply control and an additional gas supply control by using the processing gas supply unit and the additional gas supply unit, respectively, wherein the additional gas supply control includes a control that supplies the additional gas at an initial flow rate greater than a set flow rate and then at the set flow rate after a lapse of a period of time.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention will become apparent from the following description of preferred embodiments, given in conjunction with the accompanying drawings, in which:

FIG. 1 shows a cross sectional view of a configuration example of a substrate processing apparatus in accordance with an embodiment of the present invention;

FIG. 2 describes a block diagram of a configuration example of a gas supply system in accordance with the embodiment of the present invention;

FIG. 3 illustrates timing of an additional gas supply control in performing an additional gas supply process in accordance with the embodiment of the present invention;

FIG. 4 provides a graph showing experimental data of an additional gas supply process performed at a specific initial flow rate;

FIG. 5 presents a graph illustrating experimental data of an additional gas supply process performed at another initial flow rate;

FIG. 6 represents a graph describing experimental data of an additional gas supply process performed at the initial flow rate of FIG. 4 while changing a line diameter and the like;

FIG. 7 offers a graph showing experimental data of an additional gas supply process performed at the initial flow rate of FIG. 5 while changing a line diameter and the like;

FIG. 8 provides a block diagram of a configuration example of a control unit in accordance with the embodiment of the present invention;

FIG. 9 depicts a configuration example of a data table of gas supply process data of FIG. 8;

FIG. 10 describes a flowchart of a specific example of an initial flow rate determining process in accordance with the embodiment of the present invention;

FIG. 11 illustrates a flowchart of a specific example of processes to be executed after the initial flow rate determining process;

FIG. 12 is a graph showing a result of an experiment of supplying an additional gas by the additional gas supply process in accordance with the embodiment of the present invention;

FIG. 13 presents a flowchart of a specific example of an initial flow rate determining process performed while considering a maximum allowable flow rate of an additional gas line;

FIG. 14 provides a block diagram of another configuration example of the gas supply system in accordance with the embodiment of the present invention;

FIG. 15 illustrates another configuration example of the data table of the gas supply process data of FIG. 8;

FIG. 16 represents a flowchart of another specific example of the initial flow rate determining process in accordance with the embodiment of the present invention; and

FIG. 17 offers a flowchart of another specific example of the initial flow rate determining process performed while considering the maximum allowable flow rate of the additional gas line.

Claims

1. A gas supply system for supplying a gas into a processing chamber for processing a substrate to be processed, the system comprising: a processing gas supply unit for supplying a processing gas for processing the substrate to be processed;a processing gas supply line for allowing the processing gas from the processing gas supply unit to flow therein;a first and a second branch line branched from the processing gas supply line to be connected with different portions of the processing chamber;a branch flow control unit for controlling branch flows of the processing gas distributed from the processing gas supply line to the first and the second branch line based on inner pressures of the first and the second branch line, respectively;an additional gas supply unit for supplying an additional gas;an additional gas supply line, joining the second branch line at a downstream side of the branch flow control unit, for allowing the additional gas from the additional gas supply unit to flow therein; anda control unit for performing, before processing the substrate to be processed, a processing gas supply control and an additional gas supply control by using the processing gas supply unit and the additional gas supply unit, respectively,wherein the additional gas supply control includes a control that supplies the additional gas at an initial flow rate greater than a set flow rate and then at the set flow rate after a lapse of a period of time.

2. The gas supply system of claim 1, wherein the initial flow rate is predetermined based on a volume of the additional gas supply line in which the additional gas flows and the inner pressure of the second branch line into which the additional gas from the additional gas supply line flows.

3. The gas supply system of claim 2, wherein the initial flow rate is predetermined to be a maximum flow rate required for an inner pressure of the additional gas supply line to reach the inner pressure of the second branch line at the lapse of the period of time.

4. The gas supply system of claim 3, wherein the additional gas supply unit includes an additional gas line connected with an additional gas supply source, and wherein the additional gas supply control includes a control that sets, if the initial flow rate exceeds a maximum allowable flow rate in the additional gas line, the maximum allowable flow rate as the initial flow rate and lengthens the period of time to compensate for the reduction of the initial flow rate.

5. The gas supply system of claim 4, wherein the period of time is determined to be a time required for the inner pressure of the additional gas supply line to reach the inner pressure of the second branch line when supplying the additional gas at the maximum allowable flow rate set as the initial flow rate.

6. The gas supply system of claim 1, wherein a volume of the additional gas supply line is smaller than that of the second branch line.

7. The gas supply system of claim 1, wherein the first branch line is arranged to supply the processing gas flowing therein toward a central region on a surface of the substrate disposed in the processing chamber, and the second processing gas branch line is arranged to supply the processing gas flowing therein toward a peripheral region on the surface of the substrate.

8. A gas supply system for supplying a gas into a processing chamber for processing a substrate to be processed, the system comprising: a processing gas supply unit for supplying a processing gas for processing the substrate to be processed;a processing gas supply line for allowing the processing gas from the processing gas supply unit to flow therein;a first and a second branch line branched from the processing gas supply line to be connected with different portions of the processing chamber;a branch flow control unit for controlling branch flows of the processing gas distributed from the processing gas supply line to the first and the second branch line based on inner pressures of the first and the second branch line, respectively;an additional gas supply unit having a plurality of additional gas lines respectively connected with additional gas sources, downstream sides of the additional gas lines being joined together;an additional gas supply line, joining the second branch line at a downstream side of the branch flow control unit, for allowing additional gases from the additional gas supply unit to flow therein; anda control unit for performing, before processing the substrate to be processed, a processing gas supply control and an additional gas supply control by using the processing gas supply unit and the additional gas supply unit, respectively,wherein the additional gas supply control includes a control that supplies an additional gas in each additional gas line at an initial flow rate greater than a set flow rate in each additional gas line and then at the set flow rate after a lapse of a period of time.

9. The gas supply system of claim 8, wherein the initial flow rate in each additional gas line is obtained such that a ratio of the initial flow rate in each additional gas line to a total initial flow rate in whole additional gas lines is equal to a ratio of a set flow rate in said each additional gas line to a total set flow rate in the whole additional gas lines, the total initial flow rate being a predetermined maximum flow rate required for an inner pressure of the additional gas supply line to reach the inner pressure of the second branch line after the lapse of the period of time.

10. The gas supply system of claim 9, wherein the additional gas supply control includes a control of setting, in case an initial flow rate in any additional gas line exceeds a maximum allowable flow rate thereof, the maximum allowable flow rate as the initial flow rate in said any additional gas line and redetermining an initial flow rate in each remaining additional gas line and the period of time.

11. A substrate processing apparatus comprising: a processing chamber for processing a substrate to be processed;a gas supply system for supplying a gas into the processing chamber; anda control unit for controlling the gas supply system,wherein the gas supply system includes: a processing gas supply unit for supplying a processing gas for processing the substrate to be processed;a processing gas supply line for allowing the processing gas from the processing gas supply unit to flow therein;a first and a second branch line branched from the processing gas supply line to be connected with different portions of the processing chamber;a branch flow control unit for controlling branch flows of the processing gas distributed from the processing gas supply line to the first and the second branch line based on inner pressures of the first and the second branch line, respectively;an additional gas supply unit for supplying an additional gas; andan additional gas supply line, joining the second branch line at a downstream side of the branch flow control unit, for allowing the additional gas from the additional gas supply unit to flow therein, andwherein the control unit performs, before processing the substrate to be processed, a processing gas supply control and an additional gas supply control by using the processing gas supply unit and the additional gas supply unit, respectively, wherein the additional gas supply control includes a control that supplies the additional gas at an initial flow rate greater than a set flow rate and then at the set flow rate after a lapse of a period of time.

12. The substrate processing apparatus of claim 11, wherein the initial flow rate is predetermined based on a volume of the additional gas supply line in which the additional gas flows and the inner pressure of the second branch line into which the additional gas from the additional gas supply line flows.

13. The substrate processing apparatus of claim 12, wherein the initial flow rate is predetermined to be a maximum flow rate required for an inner pressure of the additional gas supply line to reach the inner pressure of the second branch line at the lapse of the period of time.

14. A gas supply method for use with a gas supply system for supplying a gas into a processing chamber for processing a substrate to be processed, wherein the gas supply system includes a processing gas supply unit for supplying a processing gas for processing the substrate to be processed; a processing gas supply line for allowing the processing gas from the processing gas supply unit to flow therein; a first and a second branch line branched from the processing gas supply line to be connected with different portions of the processing chamber; a branch flow control unit for controlling branch flows of the processing gas distributed from the processing gas supply line to the first and the second branch line based on inner pressures of the first and the second branch line, respectively; an additional gas supply unit for supplying an additional gas; and an additional gas supply line, joining the second branch line at a downstream side of the branch flow control unit, for allowing the additional gas from the additional gas supply unit to flow therein, the method comprising the steps of, before processing the substrate to be processed: performing a control of supplying the processing gas at a first set flow rate from the processing gas supply unit; andperforming a control of supplying the additional gas at an initial flow rate greater than a second set flow rate and then at the second set flow rate after a lapse of a period of time.

15. The gas supply method of claim 14, further comprising the step of: determining, before the step of performing the control of supplying the processing gas, the initial flow rate based on a volume of the additional gas supply line in which the additional gas flows and the inner pressure of the second branch line into which the additional gas from the additional gas supply line flows, the initial flow rate being a maximum flow rate required for an inner pressure of the additional gas supply line to reach the inner pressure of the second branch line at the lapse of the period of time.