JP3480254B2 - Dry etching method, dry etching apparatus, liquid crystal display manufacturing method, and semiconductor manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry etching method and a dry etching apparatus, and more particularly to a technique suitable for uniformly etching the surface of a substrate.
The present invention also provides a liquid using this dry etching method.
The present invention relates to a method of manufacturing a crystal display body and a method of manufacturing a semiconductor.

[0002]

2. Description of the Related Art In a manufacturing process including a thin film forming process used in a semiconductor manufacturing technique or a liquid crystal display manufacturing technique, a step of forming a thin film layer on a surface of a substrate and forming the thin film layer into an appropriate pattern There are many steps for performing a patterning process for the purpose. In the patterning step, for example, a resist layer is formed in a predetermined pattern on the surface of the thin film layer by a photolithography method or the like, and etching is performed using the resist layer as a mask.

Dry etching is one of the etching methods. For this dry etching, for example, there is a case where an apparatus provided with an electrode structure composed of a pair of parallel plate type electrodes housed in a chamber and facing each other is used. The substrate is held on the surface of one of the two opposing electrodes, and a high frequency voltage is applied between the two electrodes. An etching gas suitable for the material of the portion to be etched is introduced into the chamber. This etching gas is, for example, nitrogen gas as an inert gas, argon gas or the like, or chlorine gas as a reactive gas,
It is an appropriate mixture of oxygen gas, methane gas, various fluorinated gases and the like. The inside of this chamber is constantly kept at a constant pressure because the etching gas is introduced and exhausted by an exhaust device.

The etching gas introduced into the chamber is activated by a high frequency voltage applied between the electrodes and excited into a high energy state. The etching gas thus activated reacts with the surface of the substrate arranged on one of the electrodes, vaporizes the thin film layer or the like on the surface of the substrate, and performs etching.

[0005]

In the conventional manufacturing process, when a thin film layer is formed by a sputtering method or the like, the film thickness of the thin film layer may become nonuniform in the plane of the substrate. There is also nonuniformity in the thickness of the resist pattern formed in the process. Therefore, non-uniformity has already occurred in the state of the substrate surface when etching is performed. Further, even during etching, it is difficult to obtain in-plane uniformity of the etching rate of the substrate due to the above electrode structure.

[0006] Conventionally, efforts have been made to ensure in-plane uniformity in each process, but the current situation is that the objective has not been achieved sufficiently. Therefore, due to lack of in-plane uniformity of processing in each process,
There is a problem that it is difficult to obtain the dimensional accuracy and uniformity of the finally formed substrate surface structure.

In particular, in recent years, the size of the substrate has been increased in order to reduce the manufacturing cost, and it has been extremely difficult to obtain in-plane uniformity for such a size-enhanced substrate.

Therefore, the present invention solves the above-mentioned problems, and its problem is that in a manufacturing process including an etching process step, an etching process speed according to in-plane non-uniformity of a substrate surface and characteristics of an etching apparatus. By controlling the above, it is intended to realize a uniform surface structure.

[0009]

Means for Solving the Problems The means taken by the present invention to solve the above problems are to introduce an etching gas between opposed electrodes and to excite the etching gas by applying a high frequency voltage between the electrodes. In the dry etching method of etching the surface of the substrate arranged on one of the electrodes, an insulating shield selectively interposed between the other electrode and the substrate is arranged and treated. And

According to this means, the insulating shield is selectively interposed between the other electrode and the substrate,
Since the state and density of the activated etching gas vary depending on the region where the insulating shield is present and the region where the insulating shield is not present, the etching rate distribution can be controlled within the plane of the substrate, so that the etching amount within the plane of the substrate can be controlled. The optimum etching state can be realized by controlling.

Here, it is preferable that the insulating shield is mounted on the surface of the other electrode.

According to this means, it is possible to prevent the electric field from sneaking in, so that it is possible to control the etching rate with certainty, prevent abnormal discharge and the like, and maintain the stability of the etching state.

Further, in the previous step, a thin film layer is formed on the substrate, and a predetermined mask pattern is provided on the surface of the thin film layer, and the insulating shield is formed according to the thickness distribution of the thin film layer. Is preferably formed so as to control the etching rate distribution on the substrate.

According to this means, even if the thickness distribution is formed in the thin film layer, the insulating shield is formed so as to control the etching rate distribution in accordance with the thickness distribution, whereby the film after etching is formed. It is possible to prevent the remaining portion and the pattern width from being narrowed and perform uniform and accurate pattern formation.

Further, in the previous step, a thin film layer is formed on the substrate, and a predetermined mask pattern is provided on the surface of the thin film layer, and the insulating shield is formed according to the pattern width distribution of the mask pattern. Is preferably formed so as to control the etching rate distribution on the substrate.

According to this means, the etching rate is relatively small in the area where the pattern width of the mask pattern covering the thin film layer is small, and the etching rate is relatively large in the case where the pattern width is large. By
The influence of pattern thinning due to side etching or the like can be reduced, and the pattern accuracy can be improved.

On the other hand, a first electrode on the surface of which the substrate is disposed and a second electrode facing the first electrode are provided, and the first electrode is placed between the first electrode and the second electrode. In a dry etching apparatus for introducing an etching gas and exciting the etching gas by applying a high frequency voltage between the first electrode and the second electrode to etch the surface of one of the substrates. Is provided with an insulating shield selectively interposed between the second electrode and the substrate.

Here, the insulating shield is the second shield.
Is preferably mounted on the surface of the electrode.

In the case where an electromagnetic coil for forming a fluctuating magnetic field is separately provided between the first electrode and the second electrode, or the second electrode is an electromagnetic coil for forming a fluctuating magnetic field. There are cases.

Generally, as a dry etching apparatus for activating an internal gas by applying a high frequency voltage, plasma (PE) mode and reactive ion etching (RIE) are used.
Although there are modes, the RIE mode is not practical because the etching rate of Cr or the like is usually smaller than that of the PE mode. However, in order to compensate for the drawback, an ICP (Inductively Cou) that arranges an electromagnetic coil through which a high-frequency current flows around the chamber and can promote activation of an internal gas by a high-frequency magnetic field generated from the electromagnetic coil.
pled Plasma) method. According to this method, the etching rate can be improved.

The insulating shield is formed not only by adjusting its planar shape, but also by changing the thickness and dielectric constant of the insulating shield, or by using an insulating shield having a distribution of thickness and dielectric constant. It is also possible to control the distribution of the etching state such as the etching rate by these methods. Further, the liquid crystal display of the present invention is manufactured.
The manufacturing method is a patterning method using the dry etching method described above.
It is characterized by having a casting step. Also, semiconductor manufacturing
The manufacturing method is a patterning method using the dry etching method described above.
It is characterized by having a casting step.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram showing the structure of an etching apparatus of a first embodiment according to the present invention. Inside the chamber 10, a lower electrode 11 made of a conductive material such as a flat metal plate and an upper electrode 14 of the same material arranged in parallel above the lower electrode 11 are arranged. There is. The lower electrode 11 is a ground wire 12
Is kept at ground potential by. In addition, the upper electrode 14
Are connected to a high frequency power supply 16 by an application line 15.

A substrate 13 is placed on the surface of the lower electrode 11 and is appropriately fixed if necessary. Upper electrode 1
A shower head plate 17 formed of a conductive material and also serving as an effective electrode is fixed to the lower portion of 4, and an insulating shield 18 is attached to the central portion on the surface thereof. The shower head plate 17 is connected to a gas introduction port 19 provided in the chamber 10, and a large number of small gas discharge ports are formed on the plate surface.

The insulating shield 18 is formed of a ceramic plate having a thickness of 2 to 5 mm. The insulating shield 18 is
It is also possible to use various insulating materials other than the ceramic plate, for example, fluorine resin such as polytetrafluoroethylene or other synthetic resin plate.

As shown in FIG. 3, the insulating shield 18 is fixed to the central portion of the shower head plate 17 by a mounting screw 18a and a washer 18b made of ceramics. The mounting screw 18a is previously attached to the shower head plate 1
7 may be attached to the screw hole formed on the surface of the shower head plate 7, or alternatively, the above-mentioned gas discharge ports 17a distributed on the surface of the shower head plate 17 may be engraved with an internal thread and the internal thread is engraved. It may be fixed by screwing it into the gas outlet 17. By detachably attaching the insulating shield 18 to the shower head plate 17 which is an electrode in this way, the insulating shield can be replaced or the mounting position can be changed according to the processing step and the processing substrate. Can be done easily.

In this embodiment, since the insulating shield 18 is fixed to the central portion of the shower head plate 17, the electric field distribution between the lower electrode 11 and the upper electrode 14 is weak in the central portion, and the peripheral portion Therefore, the plasma of the etching gas is generated in the distribution shown by the dotted line in FIG. As a result, when the substrate 13 is etched, the etching rate is low in the central portion of the substrate and relatively high in the peripheral portion of the substrate. In the present embodiment, since the insulating shield blocks the gas outlet 17a of the shower head plate 17, a distribution is formed with respect to the gas supply amount as well, and the influence of the insulating shield on the etching rate distribution is further increased. Conceivable. However, by forming a through hole corresponding to the gas discharge port in the insulating shield, it is possible to maintain the in-plane uniformity of the gas supply amount.

In the above embodiment, when etching the thin film layer formed on the surface of the substrate 13, the etching amount in the central portion of the substrate is smaller than that in the case where the insulating shield 18 is not arranged, and the peripheral portion of the substrate is etched. It can be used in all cases where higher amounts are needed. An example of such a case will be described in detail later.For example, as a characteristic of the dry etching apparatus itself, when the etching rate at the central portion of the substrate is high and the etching rate at the peripheral portion of the substrate tends to be low, By applying the embodiment, the etching amount can be made uniform. Also,
The thin film layer formed in the previous step is thin in the center of the substrate,
It can also be applied to the case where it is formed thick at the peripheral portion of the substrate. Further, when the resist pattern formed after the thin film layer is formed is thin or thin in the central portion of the substrate and thick or thick in the peripheral portion of the substrate, the etching of the central portion of the substrate has a significant effect on the pattern shape. Side etching to the extent that gives
Since the side etching is less likely to cause a problem so much, the etching process according to the present embodiment reduces the side etching amount in the central portion of the substrate with respect to the peripheral portion of the substrate, thereby performing pattern formation without trouble. It will be possible.

FIG. 2 shows a schematic structure of the second embodiment in which the insulating shield 28 is attached to the peripheral portion of the shower head plate 17 so as to correspond to the peripheral portion of the substrate, contrary to the first embodiment. It is a thing. Also in the second embodiment, the structure other than the shape of the insulating shield 28 is exactly the same as that of the first embodiment. This insulating shield 28
The planar shape of is shown in FIG.

In this embodiment, contrary to the first embodiment, in a portion where the insulating shield 28 does not exist, that is, in a region where the lower electrode 11 and the upper electrode 14 face each other,
Since the plasma density in the central part is high and the plasma density in the peripheral part is low, the etching rate is high in the central part of the substrate,
The etching rate is low at the peripheral portion of the substrate. This embodiment can be widely applied when it is necessary to increase the etching amount in the central portion of the substrate and decrease the etching amount in the peripheral portion of the substrate as compared with the case where the insulating shield 28 is not attached. Therefore, contrary to the case described above, as a characteristic of the dry etching apparatus itself, when the etching rate is high in the central part and the etching rate is low in the peripheral part, the central part of the substrate is thick and the peripheral part of the substrate is thin in the thin film layer forming step. When the thin film layer is formed, the resist layer is thick or thick in the central portion of the substrate and thin or thin in the peripheral portion of the substrate. Can be used for

FIG. 5 is a process chart showing an example to which the second embodiment is applied. When the thin film layer 21 is formed on the surface of the substrate 13, the film thickness distribution of the thin film layer 21 is thick in the central part and relatively thin in the peripheral part due to the characteristics of a thin film forming device, for example, a sputtering device. There is. In such a case, the cross section of the substrate is as shown in FIG. 5A, and after the resist layers 22 and 23 are formed on the substrate, dry etching as in the conventional case is performed. As shown in FIG. 5B, a film residue is generated around the resist layer 22 in the central portion of the substrate, and conversely,
When the etching time is long, there is a high risk that side etching will proceed in the peripheral portion of the resist layer 23 in the peripheral portion of the substrate as shown in FIG.

In this embodiment, since the etching amount in the central portion of the substrate is relatively large and the etching amount in the peripheral portion of the substrate is relatively small, as shown in FIG. Can be processed.

The above embodiment can be applied to various substrates such as a semiconductor substrate and a liquid crystal glass substrate. Further, when etching these substrates themselves, the thin film layer formed on the substrate surface is etched. The present invention can be applied when etching various structures, such as when performing.

For example, in the case of manufacturing an active matrix type liquid crystal display using an MIM (metal-insulator-metal) element as an active element, a step of forming the first electrode layer below the MIM element with Ta, It can be applied to the step of forming the second electrode layer with Cr after forming an insulating film such as an anodic oxide film on the first electrode layer. Since the characteristics of the MIM element greatly change depending on the bonding area, if the pattern area of the first electrode layer or the second electrode layer varies in the plane of the substrate, uneven contrast or uneven coloring occurs in the display area. In order to prevent such a variation in the pattern area, it is necessary to compensate for the film thickness unevenness in the film forming process or the resist layer thickness unevenness in the etching process to cancel them, as described in FIG. Occurs. Conventionally, the variation in the pattern width of the electrode layer that determines the characteristics of the MIM element has been generated in the plane of the substrate by about 3 to 10%, but as a result of applying the present embodiment to this MIM element manufacturing process, The variation in pattern width remained within plus or minus 1%.

The etching rate distribution was measured when the first and second embodiments were used for Cr pattern etching. The substrate used is a glass substrate for a liquid crystal display, and a Cr film having a film thickness of 800 to 1000Å is formed thereon. The glass substrate has a rectangular planar shape of 350 mm × 300 mm and has a thickness of 1.1 mm. Dry etching was performed in plasma etching mode. However, the etching may be performed in the reactive ion etching mode, although the conditions and the device structure shown in FIGS. 1 and 2 are slightly changed. The applied power was 400 W, the etching gas was chlorine gas mixed with inert gas at 500 sccm (standard cubic cm per minute), and oxygen gas was mixed at a flow rate of 300 sccm, and the chamber internal pressure was 300 mmTorr. The gap between the electrodes was 80 mm, and the measurement was performed at room temperature (about 20 ° C.). The applied frequency is 13.56 MHz. The effective surface of the applying electrode is 500 mm square.

In the case of the first embodiment, an insulating shield 18 having a plane shape similar to that of the shower head plate 17 is fixed to the central portion of the shower head plate 17. In this experiment, an insulating shield 18 made of polytetrafluoroethylene and having a plate thickness of 2 mm was used as the material of the insulating shield.
At this time, the area of the insulating shield 18 is 30%, 60% of the total area of the shower head plate 17 (upper electrode),
The measurement was performed by changing the value to 80%. Figure 6
The results are shown in. Here, the vertical axis is the etching rate,
The horizontal axis is the area ratio of the insulating shield.

As shown in this graph, by providing the insulating shield 18, the etching rate at the central portion of the substrate is reduced, but the etching rate at the peripheral portion of the substrate is almost the same as that when the insulating shield 18 is not provided. It can be seen that the etching rate gradually increases from the central portion of the substrate to the peripheral portion of the substrate via the intermediate portion.
Moreover, when the area of the insulating shield 18 is increased,
The etching rates of the central portion of the substrate and the intermediate portion of the substrate gradually decrease.

On the other hand, in the case of the second embodiment, the outer edge of the shower head plate 17 substantially coincides with the outer edge of the shower head 17, and the shape of the inner opening is the plane shape of the shower head plate 17. Thickness 2 with a similar planar shape
A mm insulative shield 28 was attached. The material of the insulating shield is the same as that used in the experiment of FIG. At this time, similarly to the above, the area of the insulating shield 28 was changed so as to be 30%, 60%, and 80% with respect to the area of the shower head plate, and the measurement was performed. The result is shown in FIG. Here, the vertical axis is the etching rate and the horizontal axis is the area ratio of the insulating shield.

As shown in this graph, by providing the insulating shield 28, the etching rate at the peripheral portion of the substrate is reduced, but the etching rate at the central portion of the substrate is almost the same as that when the insulating shield 28 is not provided. It can be seen that the etching rate gradually increases from the peripheral portion of the substrate to the central portion of the substrate through the intermediate portion.
Moreover, when the area of the insulating shield 28 is increased,
The etching rates of the peripheral portion of the substrate and the intermediate portion of the substrate gradually decrease.

As shown in FIGS. 6 and 7, it is understood that by changing the area of the insulating shield, the distribution shape of the etching rate changing from the central portion of the substrate to the peripheral portion of the substrate can be appropriately controlled. Generally, the film thickness distribution and pattern error of the thin film layer and the resist layer formed on the substrate are caused by the distribution of the deposition rate, the distribution of the exposure illuminance, the optical characteristics at the time of exposure, etc. Since it often changes concentrically, it seems that there are many cases where the insulating shield having the quasi-concentric planar shape as in the first and second embodiments is used. However, the planar shape of the insulating shield according to the present invention is not limited to the substantially concentric shape as described above, but any shape having various planar shapes necessary for controlling the planar distribution of the etching rate may be used. Can be used for.

The insulating shield according to the present invention may be any insulator as long as it is an insulator. However, since it is used in the chamber of a dry etching apparatus, it is desirable that it has little outgassing and has heat resistance. As described above, a ceramic plate or a fluororesin is suitable.

By the way, the thickness and the dielectric constant of the insulating shield have a great influence on the electric field distribution. FIG. 8 shows the etching rate when two types of insulating shields having different thicknesses (thicknesses of 2 mm and 5 mm) having an area of 60% of the electrode area are attached to the central portion of the electrode as in the first embodiment. Show. Here, other conditions are the same as those in the experiment whose results are shown in FIG.

As shown in FIG. 8, when the thickness of the insulating shield is thin (2 mm), the difference in etching rate between the central portion of the substrate and the peripheral portion of the substrate is small, but the thickness of the insulating shield is large ( 5 mm), the difference in etching rate between the central portion of the substrate and the peripheral portion of the substrate becomes large. Therefore, the distribution of the etching rate can be controlled by changing the thickness of the insulating shield.

In this case, it is possible to control the etching rate in the region where the insulating shield intervenes by distributing the thickness of the insulating shield in a plane.
In an extreme case, by covering the entire electrode with an insulating shield having a desired thickness distribution, the etching rate itself decreases, but it is also possible to control the etching rate by the insulating shield over the entire surface of the substrate. is there.

In order to control the etching rate distribution, instead of the thickness of the insulating shield, the material may be changed to change the dielectric constant of the insulating shield. Using a material having a high dielectric constant is equivalent to using a thick insulating shield, and the etching rate can be controlled as in the case of changing the thickness.

In each of the above embodiments, the planar shapes of the electrodes and the substrate are both rectangular, and the planar shape of the insulating shield is also rectangular. However, depending on the planar shape of the substrate and the required etching characteristics. The planar shape of the insulating shield can be changed as appropriate. For example, when it is desired to change the etching characteristics concentrically with respect to a circular substrate, a concentric shape, that is, a circular or ring-shaped insulating shield can be used.

Further, in each of the above-mentioned embodiments, the insulating shield is fixed in a state in which it is in close contact with the upper electrode, but it may be arranged between the upper electrode and the substrate even if it is not in close contact with the upper electrode. . However, if it is too far from the upper electrode, the discharge wraps around, the effect is reduced, and the instability of the discharge such as an abnormal discharge may be caused. Therefore, the distance from the upper electrode is preferably small.

Further, in each of the above-described embodiments, the upper electrode is provided with the shower head plate, and the insulating shield is attached to the shower head plate. However, the etching gas is not introduced in this manner, but is introduced from the side of the electrode. You may.
Further, the gas discharge port of the shower head plate may be formed in a slit shape.

In each of the above embodiments, the etching rate distribution is formed by only one insulating shield, but a desired etching rate distribution may be formed by combining a plurality of insulating shields. That is clear.

In the above embodiment, the dry etching apparatus in the so-called PE mode in which a high frequency potential is applied to the electrode (upper electrode) facing the substrate to be etched has been described. However, a high frequency potential is applied to the electrode on which the substrate is placed. The configuration of the present invention can be similarly applied to a so-called RIE mode dry etching apparatus. However, as shown in the above embodiment, Cr
In the etching of the layer, it is difficult to obtain a sufficient etching rate by dry etching in the RIE mode, and the PE mode having a high etching rate is usually used. The ICP (Inductively Coupled Prasma) method is used for the purpose of improving the etching rate of the dry etching apparatus in the RIE mode.

FIG. 9 shows a schematic structure of an embodiment of a dry etching apparatus showing an example of a solenoid type ICP.
In this apparatus, the substrate 3 is placed inside the chamber 30.
3, a lower electrode 31 having the electrode 3 mounted thereon, an upper electrode 34 facing the lower electrode 31, a shower head 37 attached to the upper electrode 34, and an insulating shield 38 attached to the lower surface of the shower head 37. . The lower electrode 31 is connected to the high frequency power source 4 via the capacitor 41 by the application line 32.
Connected to 2.

An electromagnetic coil 46 wound in a spiral shape is arranged on the outer surface of the chamber 30, and the electromagnetic coil 46 is connected to the high frequency power source 36 via the application lines 44 and 45.
It is connected to the.

The upper electrode 34 is grounded via the ground wire 35. Further, the shower head 37 is configured to discharge the gas introduced from the gas introduction port 39 from a large number of gas discharge ports formed on the lower surface. The gas released into the chamber 30 is exhausted from a gas exhaust port 40 connected to an exhaust device (not shown).

The insulating shield 38 is the same as that shown in each of the above-mentioned embodiments, and is attached and arranged by the same method. In this dry etching system,
The fluctuating magnetic field formed by the electromagnetic coil 46 excites the electrons of the gas inside the chamber 30 to promote and maintain the discharge. Also in this dry etching apparatus, the plasma density can be adjusted by the insulating shield 38 and the distribution of the etching rate can be controlled in the same manner as described above.

FIG. 10 shows a schematic structure of another embodiment of the dry etching apparatus as an example of the spiral type ICP. In this apparatus, only the lower electrode 51 is provided inside the chamber 50, and the substrate 53 is placed on the upper surface thereof. The lower electrode 51 is connected to a high frequency power supply 62 via a capacitor 61 by an application line 52.
The chamber 50 has a gas inlet 59 and a gas outlet 6
0 is formed.

A spiral electromagnetic coil 66 is arranged on the outer surface of the upper wall of the chamber 50. The electromagnetic coil 66 is connected to the high frequency power source 56 via the application lines 64 and 65.
It is connected to the.

In this embodiment, the electrode (upper electrode) facing the substrate 53 is not provided separately from the chamber 50, but instead, the upper wall surface of the chamber 50 facing the lower electrode 51 is provided. Acts as a substantial electrode. In this embodiment, an electromagnetic coil 66 is further installed outside the upper wall surface of the chamber 50 facing the substrate 53. Also in this embodiment, the lower electrode 51
A high frequency voltage is applied between the chamber 50 and the upper wall surface of the chamber 50, and the fluctuating magnetic field generated from the electromagnetic coil 66 excites the gas introduced into the chamber 50 to promote and maintain the generation of plasma. It has become.

Also in this embodiment, by providing the insulating shield 58 on the wall surface of the chamber 50 facing the substrate 53, the in-plane distribution of the etching rate with respect to the substrate 53 can be controlled.

In this embodiment, the electromagnetic coil 66 installed on the upper surface of the chamber is of a spiral type, but as long as it is possible to generate a high-frequency fluctuating magnetic field in the chamber, various patterns can be used. Can be formed.

[0059]

As described above, the present invention has the following effects.

According to the present invention, the insulating shield selectively intervenes between the other electrode and the substrate, so that the state and density of the activated etching gas intervene in the region where the insulating shield intervenes. Because it changes with the area that does not
Since the etching rate distribution can be controlled within the surface of the substrate, the etching amount can be controlled within the surface of the substrate to realize an optimum etching state.

According to the present invention, since it is possible to prevent the electric field from wrapping around, it is possible to reliably control the etching rate, prevent abnormal discharge and the like, and maintain the stability of the etching state.

According to the present invention, even if the thickness distribution is formed in the thin film layer, the insulating shield is formed so as to control the etching rate distribution according to the thickness distribution, so that the film after etching is formed. It is possible to prevent the remaining portion and the pattern width from being narrowed and perform uniform and accurate pattern formation.

According to the present invention, the etching rate is relatively small for a region having a small pattern width of the mask pattern covering the thin film layer, and the etching rate is relatively large for a large pattern width. As a result, it is possible to reduce the influence of pattern thinning due to side etching or the like, and it is possible to improve the pattern accuracy.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a schematic structure of a first embodiment of a dry etching apparatus according to the present invention.

FIG. 2 is a schematic configuration diagram showing a schematic structure of a second embodiment of a dry etching apparatus according to the present invention.

FIG. 3 is a bottom view of the upper electrode for showing the planar shape of the insulating shield of the first embodiment.

FIG. 4 is a bottom view of the upper electrode for showing the planar shape of the insulating shield according to the second embodiment.

FIG. 5 is a substrate cross-sectional view (a) showing a substrate surface structure before an etching step, substrate cross-sectional views (b) and (c) showing a conventional substrate surface structure after etching, and etching according to an embodiment of the present invention. It is a board sectional view (d) showing the substrate surface structure after.

FIG. 6 is a graph showing the etching rate with respect to the area ratio of the insulating shield in the first embodiment for each of the substrate central portion, the substrate intermediate portion, and the substrate peripheral portion.

FIG. 7 is a graph showing the etching rate with respect to the area ratio of the insulating shield in the second embodiment for each of the substrate central portion, the substrate intermediate portion, and the substrate peripheral portion.

FIG. 8 is a graph showing the etching rate when the thickness of the insulating shield is changed in the first embodiment for each of the substrate central portion, the substrate intermediate portion, and the substrate peripheral portion.

FIG. 9 is a schematic configuration diagram showing an embodiment of another dry etching apparatus according to the present invention.

FIG. 10 is a schematic configuration diagram showing an embodiment of still another dry etching apparatus according to the present invention.

[Explanation of symbols]

10 chambers 11 Lower electrode 13 board 14 Upper electrode 17 Shower head board 18,28 Insulation shield

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-291983 (JP, A) JP-A-8-88190 (JP, A) JP-A-56-69374 (JP, A) JP-A-7- 228985 (JP, A) JP 6-132258 (JP, A) JP 8-264296 (JP, A) JP 6-120176 (JP, A) JP 11-61452 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) C23F 4/00 H01L 21/3065

Claims (6)

(57) [Claims] 1. An etching gas is introduced between opposed electrodes.
And applying a high-frequency voltage between the electrodes.
Exciting a etching gas, placed on one of the electrodes
Etching the surface of the substrateThe thing When a thin film layer is formed on the substrate in the previous step
In addition, a predetermined mask pattern is provided on the surface of the thin film layer.
Has been An insulating shield is provided between the other electrode and the substrate.
The pattern of the mask pattern is selectively interposed.
The etching rate distribution on the substrate is controlled according to the width distribution.
It is arranged to control Drayer characterized by
How to touch. 2. The dry etching method according to claim 1, wherein the insulating shield is attached on the surface of the other electrode. 3. A first electrode on a surface of which a substrate is disposed, and a second electrode facing the first electrode, wherein the first electrode is disposed between the first electrode and the second electrode. In a dry etching apparatus for introducing an etching gas and exciting the etching gas by applying a high frequency voltage between the first electrode and the second electrode to etch the surface of one of the substrates. , form a variable magnetic field between the second electrode includes an insulating shield which selectively interposed between the substrate, the first electrode and the second electrode
A dry etching device characterized in that a separate electromagnetic coil is provided . 4. A first electrode having a substrate disposed on a surface thereof, and a second electrode facing the first electrode, wherein the first electrode and the second electrode are provided between the first electrode and the second electrode. In a dry etching apparatus for introducing an etching gas and exciting the etching gas by applying a high frequency voltage between the first electrode and the second electrode to etch the surface of one of the substrates. And an insulating shield selectively interposed between the second electrode and the substrate , the second electrode being an electromagnetic coil that forms a fluctuating magnetic field.
Dry etching apparatus, characterized in that that. 5. A method of manufacturing a liquid crystal display, comprising a patterning step using the dry etching method according to claim 1 . 6. A method of manufacturing a semiconductor, comprising a patterning step using the dry etching method according to claim 1 .