KR20000015476A - Method for controlling internal temperature of process tube for semiconductor device fabrication - Google Patents

Abstract

PURPOSE: The present invention is intended to provide an internal temperature control method to form a specific film such as an oxide film and a nitride film whose uniformity on a wafer is improved. CONSTITUTION: The method comprises a first stabilization step, a temperature rise step, a process step, a temperature fall step and a second stabilization step. The process step is divided into several process steps that after the internal temperature of a process tube decreases to a specific temperature from a specific temperature with a constant rate, the decreased temperature is maintained, or the process step decreases the internal temperature of the process tube to a specific temperature from a specific temperature, or the process step comprises a first process maintaining the internal temperature of the process tube to a specific temperature for a fixed time and a post process step of decreasing the specific temperature to other specific temperature with a constant rate.

Description

Internal temperature control method of process tube for semiconductor device manufacturing

The present invention relates to a method for controlling the internal temperature of a process tube for manufacturing a semiconductor device, and more particularly, to an internal temperature control method for a process tube for manufacturing a semiconductor device capable of forming a specific film having improved uniformity by controlling the internal temperature of the process tube. will be.

In general, a deposition process such as a low pressure chemical vapor deposition process in a semiconductor device manufacturing process includes a heating device capable of controlling an internal temperature externally and a process gas supply pipe capable of supplying a plurality of process gases to one side. The wafer is processed in a vertical or horizontal process tube, and the wafer in which the deposition process is performed in the vertical process tube is loaded on a boat installed on the bottom of the quartz tube, and then the boat moves upward. It is injected into the process tube, and inside the quartz tube, a specific film such as an oxide film or a nitride film is formed on the wafer by depositing a reaction product formed by pyrolyzing the process gas supplied into the process tube at a high temperature through the process gas supply pipe on the wafer. do.

In addition, a diffusion process such as an oxidation process of a semiconductor device manufacturing process may be performed in a vertical or horizontal process tube in which a heating device that can adjust an internal temperature to the outside and a plurality of process gas supply pipes to supply process gas to one side are formed. The wafer is subjected to the oxidation process in the vertical process tube is loaded in a boat installed on the bottom of the process tube, and then injected into the process tube as the boat moves upward, the process inside the quartz tube An oxide film is formed on the wafer by inducing a chemical reaction between the oxygen gas supplied through the gas supply pipe and the wafer made of silicon (Si).

1 is a graph illustrating an internal temperature control method of a conventional process tube for manufacturing a semiconductor device in which an oxide film is formed on a wafer.

Referring to Figure 1, the internal temperature is adjusted to about 650 ℃ by a heating apparatus, a plurality of wafers are loaded into the process tube inside the process tube is supplied a certain amount of auxiliary gas, such as nitrogen gas, and then waiting for a predetermined time The first stabilization step is performed. In the first stabilization step, a process of checking process conditions and the like of the process equipment is performed.

Next, the temperature raising step of forming the internal temperature of the process tube to 950 ℃ by raising the internal temperature of the process tube by 7.5 ℃ per minute (Minute) by controlling the heating device.

Subsequently, after the process gas such as oxygen gas is supplied into the process tube of about 950 ° C. through the process gas supply pipe, a process step of forming an oxide film on the wafer is performed by leaving the wafer for a predetermined time. The process step includes a first process step of pre-annealing the wafer at 950 ° C., a second process step of forming an oxide film on the wafer on which the first process step is performed, and the second process By performing the step, the wafer on which the oxide film is formed may be divided into a third process step of post-annealing at 950 ° C.

Next, the temperature dropping step of stopping the supply of the process gas, such as oxygen gas, by adjusting the heating device to lower the internal temperature of the process tube by about 3.3 ℃ per minute to form the internal temperature of the process tube to 650 ℃ Perform

Finally, after discharging the boat loaded with a plurality of wafers inside the process tube on which the temperature lowering step is performed to the outside of the process tube, the second stabilization step of maintaining the internal temperature of the process tube at 650 ° C. for a predetermined time is performed. do. In the second stabilization step, a subsequent wafer is added.

However, since a heating device for controlling the internal temperature of the process tube is provided outside the process tube, the temperature of the wafer rises from the edge of the wafer introduced into the process tube toward the center, and the process gas supplied into the process tube is When comparing the edge portion of the wafer with the center portion, the edge portion of the wafer was first contacted.

Therefore, the thickness of the oxide film formed at the edge of the wafer is thicker than the thickness of the oxide film formed at the center of the wafer, resulting in poor uniformity of the oxide film formed on the wafer. There was a functioning problem.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for controlling the internal temperature of a process tube for manufacturing a semiconductor device capable of forming a specific film such as an oxide film or a nitride film with improved uniformity on a wafer.

1 is a graph illustrating an internal temperature control method of a process tube for manufacturing a conventional semiconductor device.

2 is a graph illustrating an embodiment of an internal temperature control method of a process tube for manufacturing a semiconductor device according to the present invention.

3 is a graph illustrating another embodiment of an internal temperature control method of a process tube for manufacturing a semiconductor device according to the present invention.

4 is a graph illustrating another embodiment of a method for controlling internal temperature of a process tube for manufacturing a semiconductor device according to the present invention.

In order to achieve the above object, a method for controlling internal temperature of a process tube for manufacturing a semiconductor device according to the present invention includes: manufacturing a semiconductor device in which a first stabilization step, a temperature rise step, a process step, a temperature fall step, and a second stabilization step are sequentially performed; In the method for controlling the internal temperature of the process tube, the process step is divided into a plurality of process steps to maintain the lowered temperature after the internal temperature of the process tube is lowered from a specific temperature to another specific temperature at a predetermined ratio. It features.

The process tube for manufacturing the semiconductor device may be a vertical process tube.

In addition, a diffusion process or a deposition process may be performed in the process tube for manufacturing a semiconductor device.

In addition, the internal temperature control method of the process tube for manufacturing another semiconductor device according to the present invention, the first stabilization step, the temperature rise step, the process step, the temperature drop step and the second stabilization step of the semiconductor tube manufacturing process tube In the internal temperature control method, the process step is characterized in that the internal temperature of the process tube is lowered from a specific temperature to another specific temperature at a specific ratio.

The process tube for manufacturing the semiconductor device may be a vertical process tube.

In addition, a diffusion process or a deposition process may be performed in the process tube for manufacturing a semiconductor device.

In addition, the internal temperature control method of another semiconductor device manufacturing process tube according to the present invention, the first tube stabilization step, temperature rise step, process step, temperature drop step and the second stabilization step is a semiconductor tube manufacturing process tube In the internal temperature control method of the, the process step is divided into a first process step of maintaining the internal temperature of the process tube at a specific temperature for a predetermined time and a subsequent process step of lowering the specific temperature to another specific temperature at a predetermined ratio Characterized in that it is made.

The process tube for manufacturing the semiconductor device may be a vertical process tube.

And,

A diffusion process or a deposition process may be performed inside the process tube for manufacturing a semiconductor device.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a graph showing an embodiment of an internal temperature control method of a process tube for manufacturing a semiconductor device according to the present invention.

Referring to FIG. 2, after the internal temperature is adjusted to about 650 ° C. by a heating apparatus, a boat having a plurality of wafers loaded with a plurality of wafers to be subjected to an oxidation process is introduced into a process tube into which auxiliary gas such as nitrogen gas is supplied. A first stabilization step of waiting for a predetermined time is performed. In the first stabilization step, a process of checking process conditions of the process equipment is performed.

Next, the temperature raising step of forming the internal temperature of the process tube to 950 ℃ by raising the internal temperature of the process tube by 7.5 ℃ per minute by controlling the heating device.

Subsequently, a process step of forming an oxide film on the wafer is performed by supplying a process gas such as oxygen gas into the process tube at about 950 ° C. through a process gas supply pipe. The internal temperature of the process tube in which the process step is performed is rapidly lowered by a predetermined ratio repeatedly from the initial temperature to a specific temperature, and then the first process step, the second process step, and the third process step of maintaining the lowered specific temperature. It is divided into. In the first process step, the wafer introduced into the process tube is pre-annealed at 950 ° C., and in the second process step, the wafer is substantially on the wafer at a specific temperature lowered at 950 ° C. An oxide film is formed, and in the third process step, the wafer on which the oxide film is formed at another specific temperature lowered at 950 ° C. is post-annealed. In addition, the internal temperature of the process tube in the second process step is lowered compared to the first process step, thereby forming an oxide film having high uniformity on the wafer. In other words, the wafer heated by the heater outside the process tube increases in temperature rapidly from the edge portion to the center portion, and the temperature decreases quickly from the edge portion of the wafer to the center portion. Compared with, the temperature is lowered quickly, and the temperature difference between the edge portion and the center portion decreases, thereby forming an oxide film having improved uniformity on the wafer.

Next, the supply of the process gas such as oxygen gas is stopped, and the heating apparatus is controlled to lower the internal temperature of the process tube by about 3.3 ° C. per minute to form the internal temperature of the process tube at 650 ° C.

Finally, the second stabilization step of maintaining the internal temperature of the process tube of 650 ℃ for a predetermined time after the discharge of the boat loaded with a plurality of wafers subjected to the oxidation process in the process tube in which the temperature lowering step is performed to the outside Perform In the second stabilization step, a subsequent wafer is added.

3 is a graph illustrating another embodiment of an internal temperature control method of a process tube for manufacturing a semiconductor device according to the present invention.

Referring to FIG. 3, after the internal temperature is adjusted to about 650 ° C. by a heating apparatus, a boat having a plurality of wafers loaded with a plurality of wafers to be oxidized in a process tube into which auxiliary gas, such as nitrogen gas, is supplied, is loaded. A first stabilization step of waiting for a predetermined time is performed. In the first stabilization step, a process of checking process conditions of the process equipment is performed.

Next, the temperature raising step of forming the internal temperature of the process tube to 1050 ℃ by raising the internal temperature of the process tube by 7.5 ℃ per minute by controlling the heating device.

Subsequently, a process step of forming oxide films on a plurality of wafers is performed by supplying process gas such as oxygen gas into the process tube at about 1050 ° C. through the process gas supply pipe. The internal temperature of the process tube in which the process step is performed is rapidly lowered at a predetermined ratio from the first 1050 ° C. to a specific temperature, and then the first process step, the second process step, and the third process step maintain the lowered specific temperature. It is done separately. In the first process step, the wafer introduced into the process tube is first lowered at a predetermined ratio at 1050 ° C. to be pre-annealed to an internal temperature of the process tube, and in the second process step, the wafer is pre-annealed. An oxide film is actually formed on the substrate, and in the third process step, the wafer on which the oxide film is formed is post-annealed. In addition, in the second process step, the internal temperature of the process tube is decreased by performing the first to third process steps, thereby forming an oxide film having high uniformity on the wafer. In other words, the wafer heated by the heater outside the process tube increases in temperature rapidly from the edge portion to the center portion, and the temperature decreases quickly from the edge portion of the wafer to the center portion. Compared with, the temperature is lowered quickly, and the temperature difference between the edge portion and the center portion decreases, thereby forming an oxide film having improved uniformity on the wafer.

Next, the supply of the process gas is stopped, and the heating apparatus is controlled to lower the internal temperature of the process tube by about 3.3 ° C. per minute to perform the temperature lowering step of forming the internal temperature of the process tube at 650 ° C.

Finally, after releasing the boat loaded with a plurality of wafers that have been subjected to the oxidation process from the inside of the process tube where the temperature lowering step is performed, the second stabilization to maintain the internal temperature of the process tube of 650 ℃ for a predetermined time Perform the steps. In the second stabilization step, a subsequent wafer is added.

4 is a graph illustrating another embodiment of a method for controlling internal temperature of a process tube for manufacturing a semiconductor device according to the present invention.

Referring to FIG. 4, after the internal temperature is adjusted to about 650 ° C. by a heating apparatus, a boat having a plurality of wafers loaded with a plurality of wafers to be subjected to an oxidation process is introduced into a process tube through which auxiliary gas such as nitrogen gas is supplied. A first stabilization step of waiting for a predetermined time is performed. In the first stabilization step, a process of checking process conditions of the process equipment is performed.

Next, the temperature raising step of forming the internal temperature of the process tube to 950 ℃ by raising the internal temperature of the process tube by 7.5 ℃ per minute by controlling the heating device.

Subsequently, a process gas such as oxygen gas is supplied into the process tube at about 950 ° C. through a process gas supply pipe, and then a process step of forming an oxide film on the wafer is performed. The process steps include a first process step of maintaining an internal temperature of a process tube of 950 ° C. for a predetermined time and a second process step and a third process of lowering an internal temperature of the process tube of 950 ° C. to a predetermined temperature at a predetermined ratio. It is divided into steps, that is, subsequent process steps. In the first process step, the wafer introduced into the process tube is pre-annealed at 950 ° C., in the second process step, an oxide film is actually formed on the wafer, and in the third process step, an oxide film is formed. The formed wafer is post-annealed. In addition, the internal temperature of the process tube in the second process step is lowered in the first process step, thereby forming an oxide film having high uniformity on the wafer. In other words, the wafer heated by the heater outside the process tube increases in temperature rapidly from the edge portion to the center portion, and the temperature decreases quickly from the edge portion of the wafer to the center portion. Compared with that, the temperature decreases quickly, and thus the temperature difference between the edge portion and the center portion decreases to form an oxide film having improved uniformity on the wafer.

Next, the supply of the process gas supplied into the process tube is stopped, and the heating coil is adjusted to lower the internal temperature of the process tube by about 3.3 ° C. per minute to form the internal temperature of the process tube at 650 ° C. FIG.

Lastly, after the wafer is discharged from the inside of the process tube in which the temperature lowering step is performed to the outside, a second stabilization step of maintaining the internal temperature of the process tube at 650 ° C. for a predetermined time is performed. In the second stabilization step, a subsequent wafer is added.

Therefore, according to the present invention, it is possible to prevent the malfunction of the completed semiconductor device by improving the uniformity of the specific film formed on the wafer.

Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, and such modifications and modifications are within the scope of the appended claims.

Claims (9)

In the method of controlling the internal temperature of a process tube for manufacturing a semiconductor device in which the first stabilization step, the temperature rise step, the process step, the temperature fall step and the second stabilization step are sequentially performed, The process step may be divided into a plurality of process steps for maintaining the lowered temperature after the internal temperature of the process tube is lowered from a specific temperature to another specific temperature at a predetermined ratio, the inside of the process tube for manufacturing a semiconductor device Temperature control method. The method of claim 1, The process tube for manufacturing a semiconductor device is the internal temperature control method of the process tube for manufacturing a semiconductor device, characterized in that the vertical. The method of claim 1, The internal temperature control method of the semiconductor device manufacturing process tube, characterized in that the diffusion process or the deposition process is performed in the process tube for manufacturing the semiconductor device. In the method of controlling the internal temperature of a process tube for manufacturing a semiconductor device in which the first stabilization step, the temperature rise step, the process step, the temperature fall step and the second stabilization step are sequentially performed, The process step is a method for controlling the internal temperature of a process tube for manufacturing a semiconductor device, characterized in that the internal temperature of the process tube is lowered from a specific temperature to another specific temperature at a specific ratio. The method of claim 4, wherein The process tube for manufacturing a semiconductor device is the internal temperature control method of the process tube for manufacturing a semiconductor device, characterized in that the vertical. The method of claim 4, wherein The internal temperature control method of the semiconductor device manufacturing process tube, characterized in that the diffusion process or the deposition process is performed in the process tube for manufacturing the semiconductor device. In the method of controlling the internal temperature of a process tube for manufacturing a semiconductor device in which the first stabilization step, the temperature rise step, the process step, the temperature fall step and the second stabilization step are sequentially performed, The process step may be divided into a first process step of maintaining the internal temperature of the process tube at a specific temperature for a predetermined time and a plurality of subsequent process steps of lowering the specific temperature to another specific temperature at a predetermined ratio. Internal temperature control method for process tube for semiconductor device manufacturing. The method of claim 7, wherein The process tube for manufacturing a semiconductor device is the internal temperature control method of the process tube for manufacturing a semiconductor device, characterized in that the vertical. The method of claim 7, wherein The internal temperature control method of the semiconductor device manufacturing process tube, characterized in that the diffusion process or the deposition process is performed in the process tube for manufacturing the semiconductor device.