JP2002118041A - Production line of semiconductor device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the production line of a semiconductor device which keeps the characteristics of a device to have less variance, while keeping the productivity thereof and to provide a manufacturing method of a semiconductor device. SOLUTION: This production line of a semiconductor device is provided with a gate electrode, which is formed on a P-type semiconductor substrate with a gate oxide film formed thereon in between, and an N-type source drain region in the substrate which is adjacent to the gate electrode. Furthermore, it is also provided with a measuring apparatus 21 for measure the film thickness of a dummy oxide film which is produced by an oxidizing furnace 20, and a CPU 22 which optionally selects the condition of ion implantation work, using an ion-implanting device 23 according to the measurement result of the measuring apparatus 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device production line for providing a semiconductor device with less variation in device characteristics while maintaining productivity, and a method for manufacturing such a semiconductor device.

[0002]

2. Description of the Related Art A conventional method of manufacturing a semiconductor device, in particular, various operation steps in a semiconductor device production line will be described below.

Conventionally, a gate oxide film is formed on a semiconductor substrate of a first conductivity type, for example, a P-type, a gate electrode is formed on the gate oxide film, and an N-type source is formed adjacent to the gate electrode. In a semiconductor device having a drain region formed, a manufacturing standard (eg, film thickness, line width, etc.) is determined in each step, and the process is advanced to the next step only when they fall within a desired range. . In this case, the actual processing value in the preceding process did not affect the working conditions in the subsequent process.

[0004] Here, along with the recent demand for finer design rules, the demand for reduction in processing variations in each process has become more severe.

[0005] Therefore, if the variation standard is made strict by giving priority to the device characteristics, the yield in each step is reduced, and the productivity is reduced.

Therefore, according to the present invention, it is possible to produce a semiconductor device with less variation in device characteristics while maintaining productivity by arbitrarily changing working conditions in a post-process according to the processing results in a pre-process. It is an object of the present invention to provide a method for manufacturing a line and a semiconductor device.

[0007]

In view of the above-mentioned problems, a production line of a semiconductor device according to the present invention is formed on a semiconductor layer of a first conductivity type via a gate oxide film formed on the semiconductor layer. A second conductive type source electrode formed in the semiconductor layer so as to be adjacent to the gate electrode.
In the production of a semiconductor device having a drain region, the device includes a measuring device for measuring a processing result in a previous process, and a control device for selecting a working condition in a subsequent process according to a measurement result by the measuring device. It is characterized by the following.

Accordingly, the control device selects the working conditions in the post-process according to the processing results in the pre-process measured by the measuring device, thereby maintaining the productivity and reducing the semiconductor characteristics. A production line for the equipment can be constructed.

Further, in the semiconductor device production line of the present invention, a measuring device for measuring a processing result in a previous process, a storage device for storing various operation condition data in a subsequent process, and a measuring result by the measuring device. A control device for selecting a desired operation condition from various operation condition data stored in the storage device.

[0010] Thus, the control device selects desired work conditions from various work condition data stored in the storage device in accordance with the processing results of the previous process measured by the measuring device, thereby improving productivity. In addition, it is possible to construct a production line for semiconductor devices with less characteristic variations while maintaining the above.

Further, in the semiconductor device production line of the present invention, a measuring device for measuring a processing result in a preceding process, a storage device for storing various operation condition data in a subsequent process, and a measuring result by the measuring device. A control device for selecting a desired work condition from various work condition data stored in the storage device in accordance therewith, and controlling a work in a post-process based on the desired work condition. I do.

Thus, the control device selects a desired operation condition from various operation condition data stored in the storage device in accordance with the processing results in the previous process measured by the measuring device, and selects the desired operation condition. By controlling the work in the post-process based on the conditions, it is possible to construct a production line of semiconductor devices with less characteristic variation while maintaining productivity.

Further, in the semiconductor device production line of the present invention, the preceding step is a step of forming a dummy oxide film on the semiconductor substrate, and the subsequent step is a step of removing a threshold voltage adjusting impurity from the dummy oxide film. Is a step of ion implantation.

Further, in the semiconductor device production line of the present invention, the pre-process is a step of forming a gate electrode on the semiconductor substrate via a gate oxide film, and the post-process is adjacent to the gate electrode. The method is characterized in that it is a step of ion-implanting impurities for a second conductivity type source / drain region into the substrate.

Further, a method of manufacturing a semiconductor device according to the present invention
According to the processing results in the previous process measured by the measuring device,
It is characterized in that the control device selects work conditions in a post-process.

[0016] With this, the control device selects the working conditions in the post-process according to the processing results in the pre-process measured by the measuring device, thereby maintaining the productivity and reducing the semiconductor characteristics. The device can be realized.

Further, the method of manufacturing a semiconductor device according to the present invention
According to the processing results in the previous process measured by the measuring device,
The control device selects various operation condition data in a post-process stored in the storage device.

Thus, the control device selects various operation condition data in the post-process stored in the storage device in accordance with the processing results in the pre-process measured by the measuring instrument, thereby maintaining the productivity. After that, a semiconductor device with less variation in characteristics can be realized.

Further, a method of manufacturing a semiconductor device according to the present invention
According to the processing results in the previous process measured by the measuring device,
The control device selects a desired operation condition from various operation condition data in the post-process stored in the storage device, and controls the operation in the post-process based on the desired operation condition.

According to this, the control device selects various operation condition data in the post-process stored in the storage device in accordance with the processing results in the previous process measured by the measuring instrument, and selects the desired operation condition. By controlling the work in the post-process based on this, it is possible to realize a semiconductor device with less characteristic variation while maintaining productivity.

Further, in the method of manufacturing a semiconductor device according to the present invention, the preceding step is a step of forming a dummy oxide film on the semiconductor substrate, and the subsequent step is a step of removing a threshold voltage adjusting impurity from the dummy oxide film. Is a step of ion implantation.

Further, in the method of manufacturing a semiconductor device according to the present invention, the pre-process is a step of forming a gate electrode on the semiconductor substrate via a gate oxide film, and the post-process is adjacent to the gate electrode. The method is characterized in that it is a step of ion-implanting an impurity for a source / drain region of the second conductivity type into the layer substrate.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing a semiconductor device according to an embodiment of the present invention, in particular, various working steps in a semiconductor device production line will be described with reference to the drawings.

FIGS. 1 to 6 are sectional views showing a method of manufacturing a semiconductor device according to the present invention in the order of steps.
A channel type MOS transistor structure is illustrated. Although the description of the structure of the N-channel MOS transistor is omitted, it is well known that the structure is the same except for the conductivity type.

First, in FIG. 1, for example, a desired region of a P-type semiconductor substrate 1 is approximately 450 nm by a LOCOS method.
An element isolation film 2 having a film thickness of about the same is formed.

Next, as shown in FIG. 2, the entire surface is thermally oxidized to leave about 5 μm on the substrate 1 other than the element isolation film 2.
A dummy (sacrifice) oxide film 3 having a thickness of about 0 nm is formed.

Subsequently, referring to FIG.
And an N-type well on the substrate 1 from above the dummy oxide film 3.
Impurity ion implantation for formation and threshold voltage adjustment
You. For example, phosphorous ions are accelerated at an acceleration
1.5 × 10 at pressure¹³/ Cm ^TwoN-type well under the same injection conditions
A first ion implantation for formation is performed, followed by phosphorous
The ions were charged at an acceleration voltage of about 140 KeV to 4.0 × 1
0¹²/ Cm^TwoThe second implantation for forming the N-type well under the implantation conditions of FIG.
By performing on-injection, an N-type well 4 is formed.
Acceleration voltage of about 70 KeV for boron difluoride ion
And 1.14 × 10¹³/ Cm^TwoChannel conditions
Forming channel ion implantation layer 5 by performing on-implantation
are doing.

Next, referring to FIG.
Is removed, and the entire surface is thermally oxidized, whereby the element component is removed.
On the substrate 1 other than the release film 2, a film having a thickness of about 7 nm
A gate oxide film 6 is formed. And the gate oxide film
A gate electrode 7 having a thickness of about 200 nm is formed on
To achieve. Incidentally, the gate electrode 7 of this embodiment is made of POCl. _Three
Poly-silicon doped with phosphorus for thermal conductivity
It is composed of a Kon film. Furthermore, this polysilicon
Tungsten silicide (WSix) film on the capacitor film
May be used as a polycide electrode.

Further, in FIG. 5, P-type impurities are ion-implanted so as to be adjacent to the gate electrode 7 to form low-concentration source / drain regions 8 and 9. In this step, as a P-type impurity, for example, boron difluoride ion at 2.0 × 10 ¹³ / cm 2 at an acceleration voltage of about 20 KeV.
Ion implantation is performed under the implantation condition ² .

Next, in FIG. 6, after forming an insulating film so as to cover the gate electrode 7, the insulating film is etched back to form a side wall insulating film 10 on the side wall of the gate electrode 7. I do. Then, the side wall insulating film 10
P-type impurities are ion-implanted so as to be adjacent to the source / drain regions 11 and 12 with high concentration. In this step, as a P-type impurity, for example, boron difluoride ion is added at an acceleration voltage of about 40 KeV at 2.0 × 10 ¹⁵ /
Ions are implanted under the implantation condition of cm ² .

Hereinafter, although illustration is omitted, an interlayer insulating film is formed on the entire surface of the substrate, a source electrode and a drain electrode are formed through the interlayer insulating film, and then a passivation film (not shown) is formed. Complete the device.

Here, a production line for producing the semiconductor device, which is a feature of the present invention, will be described with reference to the drawings. In the following description, an example in which channel ion implantation conditions are selected for the processed film thickness of the dummy oxide film 3 will be described.

FIG. 7 is a perspective view schematically showing a production line of the semiconductor device. First, a wafer (not shown) is taken from the upstream side.
Is transported to the diffusion furnace 20 (the transport mechanism is not shown, and a transport line is indicated by an arrow). Here, a heat treatment is performed to form a dummy oxide film 3 having a desired film thickness on the substrate 1. Is done.

Subsequently, the wafer having the dummy oxide film 3 formed thereon is transported to the next step, where the processing thickness of the dummy oxide film 3 is measured by the measuring device 21. Then, it is determined whether or not the processed film thickness of the dummy oxide film 3 falls within a desired standard. This determination is processed by the CPU 22 as a control device. That is, the CPU 22 stores the specification range data (one or several types) of the processed film thickness of the dummy oxide film stored (set) in the storage device mounted therein and the measurement value received from the measuring device 21. By comparing the result with the result, it is determined whether or not the measured result is within the standard range (step a shown in FIG. 8).

When the CPU 22 determines that the measurement result is out of the standard range, the CPU 22 performs a desired non-standard processing (step b shown in FIG. 8). Also, the CPU 22
However, if it is determined that the measurement result is within the specification range, the process proceeds to the next step.

Here, a description will be given of a case where only one type of standard thickness data of the processed film thickness of the dummy oxide film is set. The CPU 22 determines whether the dummy oxide film 3 of the processed film thickness determined to be within the specified range is set. On the other hand, after ion implantation for forming an N-type well is performed as described above, channel ion implantation is performed. In this case, the CPU 22 adjusts the threshold voltage based on one type of channel ion implantation condition set for the processed film thickness of the dummy oxide film 3 stored in the storage device. Channel ion implantation is performed.

A description will be given of the case where several types of standard thickness data of the processed film thickness of the dummy oxide film are set. First, the CPU 22 determines in which of the several types of standard range data the above-described measurement results are included. It is selected whether it corresponds (step c shown in FIG. 8). Then, channel ion implantation conditions corresponding to the desired range data are selected (FIG. 8).
In step d), the CPU 22 performs channel ion implantation for adjusting the threshold voltage based on the selected desired channel ion implantation condition (step e in FIG. 8). In FIG. 8, the ion implantation conditions for forming the N-type well are constant irrespective of the processed film thickness of the dummy oxide film.
After ion implantation for forming a mold well, channel ion implantation is performed.

FIG. 9 shows data of the acceleration voltage at the time of channel ion implantation, which is selected in accordance with the range of the processed film thickness of various dummy oxide films when the above-described channel ion implantation is performed.

For example, in this embodiment, the channel ion
As described above, the boron fluoride ion
At an accelerating voltage of about 70 KeV and 1.14 × 10¹³/
cm ^TwoAnd the injection amount. In this case, 70K
Processed film thickness of dummy oxide film 3 that can be handled by acceleration voltage of eV
Is in the range of approximately 47.5 nm to 50.5 nm,
For example, processing of the dummy oxide film 3 measured by a measuring device
If the film thickness is approximately 46.5 nm, 6
The same amount of ions is implanted at an acceleration voltage of 7 KeV.
That would be good. At this time, the following relational expression is established.
Stand up.

[0040]

(Equation 1) At this time, the channel ion implantation condition selected as described above may be displayed on the screen of the CPU 22, and the operator may switch the ion implantation condition setting switch of the ion implantation device 23 according to the instruction. ,
The CPU 22 may directly change the set value of the ion implantation condition of the ion implantation apparatus 23 and perform the ion implantation operation under the changed ion implantation condition.

Hereinafter, the wafer on which channel ion implantation has been performed as described above is transported to the next step and subjected to a predetermined operation (in this embodiment, the step of forming the gate electrode 7).

In the above-described embodiment, the case where channel ion implantation conditions are selected with respect to the processed film thickness of the dummy oxide film 3 has been described as an example. However, the present invention is not limited to this. When the ion implantation conditions for forming the source / drain are selected for the line width variation at the time of forming the electrode 7 (when the line width of the gate electrode 7 is smaller than a predetermined line width, the ion implantation amount is reduced, If the thickness is too large, the ion implantation amount must be increased.) In this case, various line width range data is stored in advance, that is, in the storage device, and based on the line width result measured by the measuring device, the CP is determined.
U22 may determine whether or not the result of the line width is within the standard range of the line width, and control may be performed so as to select a desired ion implantation condition corresponding to the desired line width range.

[0043]

According to the present invention, it is possible to arbitrarily change the working conditions in the post-process according to the processing results in the pre-process,
A semiconductor device production line capable of providing a semiconductor device with little characteristic variation while maintaining productivity can be constructed.

Further, according to the present invention, the working conditions in the post-process are arbitrarily selected according to the processing results in the preceding process, and the desired work is performed in the post-process according to the processing results. A semiconductor device with less variation in characteristics can be manufactured while maintaining productivity.

[Brief description of the drawings]

FIG. 1 is a sectional view illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating the method for manufacturing the semiconductor device according to one embodiment of the present invention;

FIG. 6 is a sectional view illustrating the method for manufacturing the semiconductor device according to one embodiment of the present invention;

FIG. 7 is a perspective view showing a production line for a semiconductor device according to an embodiment of the present invention.

FIG. 8 is a flowchart illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 9 is a diagram showing acceleration voltage data selected at the time of channel ion implantation according to the processed film thickness of the dummy oxide film.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiro Yoshitake 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. F-term (reference) 5F040 DA06 EC01 EC07 EC13 EF02 EK01 FA03 FB02 FC00

Claims (10)

[Claims] A gate electrode formed on the semiconductor layer via a gate oxide film formed on the semiconductor layer of the first conductivity type; and a gate electrode formed in the semiconductor layer so as to be adjacent to the gate electrode. In a production line of a semiconductor device having a source / drain region of the second conductivity type, a measuring device for measuring a processing result in a previous process, and an operation condition in a subsequent process are selected according to a result of measurement by the measuring device. A production line for semiconductor devices, comprising: a control device. 2. A gate electrode formed on the semiconductor layer via a gate oxide film formed on the semiconductor layer of the first conductivity type, and formed in the semiconductor layer adjacent to the gate electrode. In a production line of a semiconductor device having a source / drain region of the second conductivity type, a measuring device for measuring a processing result in a previous process, a storage device for storing various operation condition data in a subsequent process, and the measuring device A control device for selecting a desired operation condition from various operation condition data stored in the storage device according to the measurement result of the semiconductor device. 3. A gate electrode formed on the semiconductor layer via a gate oxide film formed on the semiconductor layer of the first conductivity type, and formed in the semiconductor layer adjacent to the gate electrode. In a production line of a semiconductor device having a source / drain region of the second conductivity type, a measuring device for measuring a processing result in a previous process, a storage device for storing various operation condition data in a subsequent process, and the measuring device A control device for selecting a desired work condition from various work condition data stored in the storage device according to the measurement result according to the above, and controlling a work in a post-process based on the desired work condition. A semiconductor device production line, characterized in that: 4. The method according to claim 1, wherein the first step is a step of forming a dummy oxide film on the semiconductor layer, and the second step is a step of ion-implanting an impurity for adjusting a threshold voltage from the dummy oxide film. The production line of a semiconductor device according to claim 1, claim 2 or claim 3. 5. The method according to claim 1, wherein the pre-process is a step of forming a gate electrode on the semiconductor layer via a gate oxide film, and the post-process is a step of forming a second conductive type source in the semiconductor layer so as to be adjacent to the gate electrode. 4. The semiconductor device production line according to claim 1, wherein the step of ion-implanting a drain region impurity is performed. 6. A semiconductor having a gate electrode formed on a gate oxide film on a semiconductor layer of a first conductivity type and a source / drain region of a second conductivity type formed adjacent to the gate electrode. In the manufacturing method of the device, according to the processing results in the previous process measured by the measuring device,
A method for manufacturing a semiconductor device, wherein a control device selects an operation condition in a post-process. 7. A semiconductor having a gate electrode formed on a gate oxide film on a semiconductor layer of a first conductivity type, and a source / drain region of a second conductivity type formed adjacent to the gate electrode. In the manufacturing method of the device, according to the processing results in the previous process measured by the measuring device,
A method of manufacturing a semiconductor device, wherein a control device selects various operation condition data in a post-process stored in a storage device. 8. A semiconductor having a gate electrode formed on a gate oxide film on a semiconductor layer of a first conductivity type, and a source / drain region of a second conductivity type formed adjacent to the gate electrode. In the manufacturing method of the device, according to the processing results in the previous process measured by the measuring device,
A semiconductor device, wherein a control device selects a desired operation condition from various operation condition data in a post-process stored in a storage device, and controls a post-process operation based on the desired operation condition. Manufacturing method. 9. The method according to claim 1, wherein the pre-process is a process of forming a dummy oxide film on the semiconductor layer, and the post-process is a process of ion-implanting a threshold voltage adjusting impurity from the dummy oxide film. 9. The method for manufacturing a semiconductor device according to claim 6, wherein 10. The method according to claim 1, wherein the pre-process is a step of forming a gate electrode on the semiconductor layer via a gate oxide film, and the post-process is a step of forming a second conductive type source / electrode in the semiconductor layer so as to be adjacent to the gate electrode. 9. The method of manufacturing a semiconductor device according to claim 6, further comprising the step of ion-implanting an impurity for a drain region.