KR20090044420A

KR20090044420A - Plasma process apparatus used for manufacturing semiconductor device

Info

Publication number: KR20090044420A
Application number: KR1020070110513A
Authority: KR
Inventors: 최용규
Original assignee: 주식회사 하이닉스반도체
Priority date: 2007-10-31
Filing date: 2007-10-31
Publication date: 2009-05-07

Abstract

An upper electrode matrix disposed on an upper side of a process chamber in which a wafer is mounted and having unit electrodes independent of positional movement therebetween, and a lower electrode disposed opposite to the upper electrode matrix; And a power source connected to the upper electrode matrix and the lower electrode for plasma excitation.

Plasma, etching, deposition, uniformity, induced magnetic field

Description

Plasma process apparatus for semiconductor device manufacturing

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the manufacture of semiconductor devices, and more particularly, to a process apparatus using plasma.

Thin film deposition and etching processes have been used to integrate circuits constituting semiconductor devices on wafers. Process apparatuses using plasma in the deposition or selective etching of such thin films are used. The plasma processing apparatus includes a process chamber that provides a space and an environment in which a wafer process such as etching or deposition is performed, and an upper electrode is disposed above the process chamber and a lower electrode is disposed below the process chamber. . When RF (Radio Frequency) power is applied to the upper and lower electrodes, an induced magnetic field is induced between the upper and lower electrodes, and the process reaction gas is excited to the plasma state by the induced induced magnetic field change. The excited plasma arrives on the wafer, and reactive ions and the like in the plasma process react, whereby an etching reaction or a deposition reaction is performed on the wafer.

Since the thin film is substantially etched or deposited by the reactive ions produced by the excited plasma, the plasma process, such as etching or deposition, is dependent on the density or concentration and energy of the reactive ions. The density or concentration and energy of these reactive ions are substantially influenced by the plasma generation density, which is influenced by the voltage applied to the upper and lower electrodes and thus the distribution of the induced magnetic field.

The density distribution of the plasma or the concentration distribution of the reactive ions and the energy distribution reaching the wafer (or the etching target layer or the deposition target layer deposited on the wafer) are preferably induced to have a uniform distribution throughout the wafer region. Depending on the position of, different distributions can be seen. As a result, the etching (or deposition) speed may vary for each wafer region, so that a variation in the pattern size or the thickness of the deposited film may occur, which may result in deterioration or non-uniformity of product characteristics. In some cases, rather than inducing a uniform plasma density over the entire wafer area, it may be advantageous for pattern size uniformity or product characteristic uniformity to induce different plasma density for each wafer area.

While it is advantageous to the device characteristics or process uniformity to adjust or modify the distribution of the reaction plasma density induced on the wafer according to the process, the process of modifying the distribution of the reaction plasma density on a process-by-process basis allows the upper and lower electrodes to be substantially flat. Planar plate) in the form of a fixed state is practically difficult. Since the plasma is generated by using a fixed type of electrode, it is possible to change the power or bias of the plasma generating power source or to change the vacuum of the process chamber as a means for controlling the plasma distribution or characteristics. The solution may be limited. Nevertheless, it is substantially difficult to change the plasma distribution more freely per wafer region. Accordingly, in order to more precisely realize an etch bias and an etching uniformity, an improvement of a plasma processing apparatus capable of improving the uniformity of the plasma distribution or otherwise changing the plasma distribution for each wafer region is required.

An object of the present invention is to provide a plasma processing apparatus for manufacturing a semiconductor device capable of changing the plasma distribution for each wafer region.

One aspect of the invention, the process chamber (chamber) to which the wafer is mounted; An upper electrode matrix installed above the process chamber and arranged with unit electrodes having independent positional movements; A lower electrode disposed to face the upper electrode matrix and supporting the wafer; And a power source connected to the upper electrode matrix and the lower electrode for plasma excitation.

Connection axes connected to each of the unit electrodes of the upper electrode matrix; A driving unit driving the connecting shafts independently; And an electrode position adjusting unit configured to independently adjust the separation distance between the lower electrode and the unit electrodes by the driving unit by independently driving the connecting shafts up or down by the unit electrodes. present.

The electrode position adjusting unit may control the driving unit to drive the unit electrodes to move up, down, or horizontally independently of each other according to the set position information of the unit electrodes.

An embodiment of the present invention may provide a plasma processing apparatus for manufacturing a semiconductor device capable of changing the plasma distribution for each wafer region.

1 is a view for explaining a plasma processing apparatus for manufacturing a semiconductor device according to an embodiment of the present invention. Referring to FIG. 1, a plasma processing apparatus according to an embodiment of the present invention may include a flat lower electrode 300 on which a process chamber 100 and a wafer 200 are mounted and supported. have. An upper electrode matrix 400 is installed on an upper side of the process chamber 100 opposite to the lower electrode 300. The upper electrode matrix 400 is configured by arranging unit electrodes 401 having independent positional movements.

RF power is applied to the upper electrode matrix 400 and the lower electrode 300 through the power supply 500, and the inside of the process chamber 100, that is, the upper electrode matrix 400 is applied by the applied RF power. The induced magnetic field is induced below. In such an induced magnetic field, a reaction gas, for example, a deposition source gas is introduced through a first gas injector 111 and excited in a plasma state in a deposition process. In this case, an inert gas to be used as an atmosphere or a carrier may be introduced into another second gas injector 113. The gas injectors 111 and 113 are installed in the process chamber 100 as supply means for introducing a reactive gas or an inert gas into the process chamber 100.

The upper electrode matrix 400 is configured by arranging unit electrodes 401, and each of the unit electrodes 401 is configured to be moved independently of each other. The unit electrode 401 is configured to be independently moved in the X-, Y-, and Z-axis directions in the X-Y-Z coordinate system. To this end, the individual unit electrodes 401 are configured to be independently separated from each other, and a driving unit 405 for driving the respective unit electrodes 401 for individual movement is introduced. The driving unit 405 may include a linear motor for driving the fine movement of the unit electrode 401. In addition, the electrode position adjusting unit is configured to drive the position information of the unit electrode 401 inputted to the electrode position adjusting unit 407 or the position of the unit electrodes 401 according to information prepared by a map based on the XYZ coordinate system. 407 and driver 405 may be configured to include an encoder (decoder) and decoder (decoder) for decoding such information.

Accordingly, the operator inputs the position coordinates of the unit electrodes 401 determined to be suitable in the etching process or the deposition process to be performed, as the position information map data, to the electrode position adjusting unit 407, and the electrode position adjusting unit ( The 407 may drive the driving unit 405 according to this information to adjust individual positions of the unit electrodes 401. The driving of the unit electrode 401 for position adjustment may be performed by the movement of the connecting shafts 403 connecting the driving unit 405 and the individual unit electrodes 401. Individual motors constituting the driving unit 405 are connected to the respective connecting shafts 403 to transmit different driving operations of the motors to the unit electrode 401 to adjust the position of the unit electrode 401. Accordingly, the unit electrodes 401 may be maintained at different intervals from each other, or may be maintained at different heights.

On the other hand, as described above, the unit electrodes 401 are configured to operate independently of each other, but are connected to the power source 500 in an electrically connected state. Accordingly, a voltage or current from the same power source 500 is applied to the entire unit electrode 401, thereby generating an electric field in a state in which the individual unit electrodes 401 are electrically coupled, and generating an electric field. Magnetic field is induced. However, since the position and height of the unit electrodes 401 with respect to the lower electrode 300 may be different from each other, the spacings d1 and d2 between the lower electrodes 300 may be changed.

Since the first spacing d1 and the second spacing d2 are adjusted differently, the distribution of the induced magnetic field is also changed accordingly, and the plasma density generated is also changed. Since the mutual spacing between the unit electrodes 401 is also different from each other in a dense and more spaced state, the plasma density is also different. By using these points, the density of the plasma induced under the unit electrodes 401 may be partially differently changed by changing the position of the unit electrodes 401, the mutual separation interval, and the separation interval with the lower electrode 300. have. Accordingly, the density of the entire plasma arriving on the wafer 200 may be induced uniformly over the entire area of the wafer 200, and also different plasma density distributions may be controlled for each area of the wafer 200. It may be.

For example, in the etching process, a pattern size or pattern density to be formed on the wafer 200, an area to be etched, an area of an open area in which there is no pattern to be etched, and the like may be different for each area of the wafer 200. Can be. Therefore, in consideration of etching bias or etching result pattern size (CD) uniformity for each region, when it is advantageous to implement different etching rates for each region of the wafer 200, the plasma density distribution is induced such that the difference in the etching rates is induced. The location information maps of the unit electrodes 401 are created such that is differently induced for each region of the wafer 200. Thereafter, the driving unit 405 is operated based on the created location information map to adjust the position of the unit electrode 401, thereby inducing a plasma having a density distribution in accordance with the intended purpose in the process chamber 100. Therefore, more precise etching results can be realized, and also pattern uniformity can be realized. In addition, the position adjustment of the unit electrode 401 may be suitably performed for each process before performing different etching processes. Thus, despite the change in the etching process, it is possible to implement uniformity of the etching results.

2 and 3 are diagrams for explaining a first embodiment of an upper electrode matrix according to an embodiment of the present invention. 2 and 3, the upper electrode matrix 401 of FIG. 1 may be configured as an array 410 of unit electrodes 411 and 413 in the form of a cylinder. That is, the arrangement of the plurality of second unit electrodes 413 in the form of a concentric cylinder (cylinder) surrounding the first unit electrode 411 in the form of a central circular rod and the first unit electrode 411 in the form of a circular rod. 410 may be configured and used as the upper electrode matrix 401. In this case, the plasma density distribution excited by the vertical movement of the unit electrodes 411 and 413 may be changed.

4 and 5 are views for explaining a second embodiment of the upper electrode matrix according to the embodiment of the present invention. 2 and 3, in the upper electrode matrix 401 of FIG. 1, the upper electrode matrix 401 of FIG. 1 has a rectangular columnar shape, and the unit electrode 431 has a rectangular or rectangular plane. It may be configured to include an array (430) in the form of a mosaic. In this case, the individual unit electrodes 431 may not only move up and down but also move left and right on a plane, and thus, spaced apart from each other may be adjusted. Thereby, it is possible to adjust the plasma density distribution more freely.

As such, in the exemplary embodiment of the present invention, the plasma density distribution may be differently adjusted for each region of the wafer 200 by setting and disposing the positions of the unit electrodes 401 of FIG. 1. Therefore, the deposition result implemented on the wafer 200 may be more uniformly induced. In addition, it is possible to improve the uniformity of the pattern size which is an etching result implemented on the wafer 200, and the uniformity of the etch bias may also be adjusted for each region, thereby improving overall.

1 is a view for explaining a plasma processing apparatus for manufacturing a semiconductor device according to an embodiment of the present invention.

2 and 3 are diagrams for explaining a first embodiment of an upper electrode matrix according to an embodiment of the present invention.

4 and 5 are views for explaining a second embodiment of the upper electrode matrix according to the embodiment of the present invention.

Claims

A process chamber in which the wafer is mounted;

An upper electrode matrix installed above the process chamber and arranged with unit electrodes having independent positional movements;

A lower electrode disposed to face the upper electrode matrix and supporting the wafer; And

And a power supply connected to the upper electrode matrix and the lower electrode for plasma excitation.

The method of claim 1,

Connection axes connected to each of the unit electrodes of the upper electrode matrix;

A driving unit driving the connecting shafts independently; And

And an electrode position adjusting unit configured to independently adjust the separation distance between the lower electrode and the unit electrodes by driving the connection shafts independently of each other by the driving units.

The method of claim 2,

The electrode position adjusting unit

And a driving unit configured to control the driving unit to move the unit electrodes up, down, or horizontally independently according to the set position information of the unit electrodes.

The method of claim 1,

The upper electrode matrix is

A first unit electrode in the form of a central circular bar; And

Plasma processing apparatus for manufacturing a semiconductor device comprising an array of a plurality of second unit electrodes in the form of a concentric cylinder (cylinder) surrounding the first unit electrode.

The method of claim 1,

The upper electrode matrix is

And the unit electrodes have a rectangular bar shape, and the unit electrodes are arranged in a moaic shape to form a rectangular or rectangular plane.

The method of claim 1,

Installed in the process chamber

And a gas injector for providing a deposition source gas for the deposition reaction to be performed on the wafer.

The method of claim 1,

Installed in the process chamber

And a gas injector for providing an etching source gas for an etching reaction to be performed on the wafer.