JPH08114440A - Film thickness measuring method and method and device for thin film formation - Google Patents

Abstract

PURPOSE: To form desired thickness of a thin film an a plate-like work with stability by converting bend quantity of the plate-like work into film thickness of the thin film formed on the plate-like work. CONSTITUTION: A reaction chamber 3 formed inside of a vacuum vessel 2 has a wafer chuck 7 at the lower part, and, on the chuck 7, a semiconductor wafer 1 of a to-be-processed member is mounted for heating to the specified temperature. Relating to bend quantity measuring parts 11 on the upper part of the vessel 2, the wafer 1 is irradiated with laser beam from a flood part 11a, and then, the reflected light is received by photodetecting part 11b. And, while the chuck 7 is moved in horizontal direction, the surface of the wafer 1 is scanned, and, based on variation in receiving position on the photodetecting part 11b in relation with variation of reflecting position on the surface of the wafer 1, the bend quantity is measured. A controlling part 12 into which it is inputted inputs correlation data of the bend quantity and thin film thickness from an inputting part 13, and then, based an the data, the bend quantity is converted into a film thickness value. Thus, desired film thickness of the thin film is formed with stability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film thickness measuring method, a thin film forming method and a thin film forming apparatus, and is particularly effective when applied to controlling the film thickness of a thin film formed on a plate-like work such as a semiconductor wafer. Regarding technology.

[0002]

2. Description of the Related Art In a so-called wafer process from surface cleaning of a semiconductor wafer (plate-like work) cut out from a silicon ingot to formation of predetermined circuit elements and formation of a cover film, for example, CVD (Chemical V
apor Deposition) technology to use chemical reactions in the gas phase, or PVD (Physical Vapor Deposition) technology to use vapor deposition or knocking out atoms by ions,
Many times, a thin film having a desired thickness is formed on a semiconductor wafer. The thickness of these thin films is about 10 nm to several μm.
The range is extremely thin.

Here, while the diameter of the semiconductor wafer is increased to 20 cm, the film thickness of the thin film formed on this semiconductor wafer tends to become thinner. Therefore,
The film forming technique for a semiconductor wafer requires forming a thinner film uniformly over a large area to a predetermined thickness.

To control the film thickness of the thin film during film formation, for example, film thickness measurement using infrared rays in the formation of a polycrystalline silicon film or a crystal oscillator in the formation of an aluminum film in the formation of a wiring layer was used. In some cases, such as film thickness measurement, the film thickness can be measured by directly measuring the film thickness during film formation, that is, by measuring the film thickness in-line.

However, for example, a silicon nitride film (Si ₃ N ₄ ) formed on a semiconductor wafer by the plasma CVD technique
When in-line measurement is not possible, the deposition rate of the thin film, that is, the deposition rate is determined from factors such as the heating temperature of the semiconductor wafer, the gas supply rate, and the gas partial pressure, and the deposition time is set from this deposition rate. Is being done.

Examples of detailed description of such a thin film forming technique include, for example, published by Dainippon Tosho Co., Ltd.,
"Silicon LSI and Chemistry" (Published October 10, 1993), P1
There are 64 to P189.

[0007]

However, not only does the deporate change depending on whether the substrate is a silicon substrate or an oxide film substrate, but also the type of semiconductor wafer, that is, the type of circuit elements formed on the semiconductor wafer and the semiconductor wafer on which it is mounted. The thickness of the film cannot be accurately controlled by the uniform method of setting the film formation time from the deposition as described above, because it also changes depending on the uniqueness of each semiconductor wafer, such as the adhesion to the stage. .

Therefore, an object of the present invention is to provide a technique capable of stably forming a thin film having a desired film thickness on a plate-like work such as a semiconductor wafer.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0010]

The typical ones of the inventions disclosed in the present application will be outlined below.

That is, the film thickness measuring method according to the present invention is
It measures the bend amount of a plate-like work on which a thin film is formed by being placed on a stage, and converts this bend amount into the film thickness of the thin film formed on the plate-like work to calculate the film thickness value of the thin film. is there. In this case, the bend amount of the plate-like work is measured from the height difference between the outer peripheral edge and the central portion of the plate-like work or the space between the stage and the plate-like work formed by the warp of the plate-like work. be able to.

The thin film forming method according to the present invention measures the bend amount of a plate-like work placed on a stage before film formation, forms a thin film on the plate-like work for a predetermined time, and measures the film thickness as described above. The film thickness of the plate-like work after film formation is measured by the method, and when the film thickness of the plate-like work reaches a desired film thickness value, the film formation is ended and the process proceeds to the next sequence. If not, the film formation is further continued until the film thickness value is reached.

A thin film forming apparatus according to the present invention forms a thin film on a plate-like work placed on a stage, and includes a bend amount measuring means for measuring the bend amount of the plate-like work and the bend amount measuring means. It has a control means for calculating the film thickness value of the thin film from the measured bend amount of the plate-like work, and a film thickness display means for displaying the film thickness value calculated by the control means.

Further, the thin film forming apparatus according to the present invention forms a thin film on a plate-like work placed on a stage, and the set film thickness value of the plate-like work, the film forming time on the plate-like work and the plate-like work. Input means for inputting the correlation data between the work bend amount and the film thickness, a bend amount measuring means for measuring the bend amount of the plate-like work, and a plate measured by the bend amount measuring means after the input film formation time has elapsed. The film thickness value of the thin film is calculated from the bend amount of the work piece, and when the film thickness value reaches the set film thickness value, the film formation is ended and the sequence is shifted to the next sequence. And a control means for continuing film formation until the film thickness value is reached.

The thin film forming apparatus according to the present invention forms a thin film on a plate-like work placed on a stage. The set film thickness value of the plate-like work, the film forming time on the plate-like work, and the plate-like work Input means for inputting the correlation data between the bend amount and the film thickness, a bend amount measuring means for measuring the bend amount of the plate-like workpiece, and a plate-like workpiece measured by the bend amount measuring means after the input film formation time has elapsed. The film thickness value of the thin film is calculated from the bend amount of, and when the film thickness value reaches the set film thickness value, the film formation is ended and the sequence is shifted to the next sequence. The film thickness value calculated by this control means and the control means for continuing the film formation until the value is reached and activating an alarm notifying the operator that the film formation time is out of the input film formation time display It is those having a thickness display unit.

A thin film forming apparatus according to the present invention forms a thin film on a plate-shaped work placed on a stage.
Input means for inputting the correlation data between the bend amount of the plate-like work and the film thickness and the correlation data between the bend amount of the plate-like work and the film stress, and a bend amount measuring means for measuring the bend amount of the plate-like work, and inputting When the film thickness value and the film stress value of the thin film are calculated from the bend amount of the plate-like work measured by the bend amount measuring means after the film formation time has elapsed, and when the film thickness value reaches the set film thickness value, While the film formation is completed and the sequence is shifted to the next sequence, if not, the film formation is continued until the set film thickness value is reached and the operator confirms that the film formation time is out of the input film formation time. And a film stress value display device for displaying a film stress value, and a film thickness display device for displaying a film thickness value calculated by the control device.

In these thin film forming apparatuses, the above-mentioned bend amount measuring means forms the bend amount of the plate-like work by the height difference between the outer peripheral end and the center of the plate-like work or the warp of the plate-like work. Can be measured from the space between the stage and the plate-like work.

[0018]

According to the above-mentioned means, the bend amount during film formation is measured by the bend amount measuring means, and the film thickness value of the thin film formed on the plate-like work is calculated by back-calculating from this bend amount. Therefore, depending on various factors such as the type of plate work and the adhesion between the plate work and the stage, the desired film can be stably applied to each plate work without being affected by the different deposition rate for each plate work. It becomes possible to form a thick thin film.

Further, since the film thickness value is calculated from the bend amount, the film thickness can be measured in-line during film formation, and workability is improved as compared with the case where film thickness measurement is performed offline after film formation. To do. At the same time, if the thickness of the formed thin film is insufficient, the film can be formed again, so that the plate-shaped workpieces after the film formation each have a desired film thickness, The process yield during film formation is improved.

[0020]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a schematic view showing a thin film forming apparatus which is an embodiment of the present invention, FIG. 2 is a front view showing a display portion provided in the thin film forming apparatus, and FIG. 3 is a control system of the thin film forming apparatus. FIG. 4 is a block diagram showing the data input to the input unit of the thin film forming apparatus, and FIG. 5 is a flowchart showing a thin film forming process by the thin film forming apparatus.

The thin film forming apparatus of this embodiment shown in FIG. 1 places a predetermined reaction gas in an electric field and collides it with accelerated electrons to generate a mixed state of ions and radicals, that is, a plasma state. A plasma CVD apparatus for forming a thin film of single crystal silicon, polycrystalline silicon, or silicon dioxide (SiO ₂ ) on the surface of a semiconductor wafer (plate-shaped work) 1. A reaction chamber 3 is formed inside a vacuum container 2 that constitutes the apparatus body. From the top of the vacuum container 2 made of quartz or the like to the reaction chamber 3
A gas supply pipe 4 is provided so as to penetrate therethrough, and for example, SiH ₄ or Si ₂ H ₄ as a reaction gas is introduced into the reaction chamber 3.

An electrode 5 for generating plasma discharge in the reaction chamber 3 is provided above the reaction chamber 3. To supply electric power to the electrode 5, one end of a high frequency power source (hereinafter referred to as “RF power source”) 6 is connected to the electrode 5. Therefore, the RF power supply 6 supplies the electrode 5 with high-frequency power of, for example, 13.56 MHz. The other end of the RF power source 6 is grounded and dropped to the ground level.

Below the reaction chamber 3, a wafer chuck (stage) 7 for mounting the semiconductor wafer 1, which is a member to be processed, is provided. A wafer chuck 7 for holding the circuit formation surface of the semiconductor wafer 1 upward is provided with a heater 8 for heating the semiconductor wafer 1 to, for example, about 200 ° C. to improve the deposition rate. Also,
The wafer chuck 7 is movable in the horizontal direction in order to move the semiconductor wafer 1 in the plane direction thereof.

In order to set the pressure in the reaction chamber 3 to a low pressure of, for example, about 0.1 Torr, an exhaust port 9 is provided in the bottom wall of the vacuum container 2 and the exhaust port 9 is provided with a vacuum pump 16.
(Fig. 3). Further, a pressure gauge 10 for measuring the pressure inside the reaction chamber 3 is attached to the vacuum container 2 in order to always maintain the inside of the reaction chamber 3 at a predetermined pressure.

A bend amount measuring section (bend amount measuring means) 11 for measuring the bend amount (warp amount) of the semiconductor wafer 1 is attached to the upper portion of the vacuum container 2. That is, the semiconductor wafer 1 which is a plate-shaped processing target cannot completely eliminate the warp of itself due to processing limitations, and the thicker the thin film formed at the time of thin film formation is, the more it receives it. The stress increases and the warp increases. Therefore, if the correlation data between the bend amount and the film thickness of the semiconductor wafer 1 is obtained in advance, the bend amount during film formation can be measured from the difference between the bend amount before film formation and the bend amount after a certain period of time. Therefore, the film thickness can be calculated. Focusing on this point, the present inventor attaches the above-described bend amount measuring unit 11 to this device.

As the bend amount measuring unit 11, a laser displacement meter is used in the illustrated case, and a projecting unit 11a for generating a visible light semiconductor laser beam (hereinafter simply referred to as "laser beam") and this projecting unit 11a are used. Light receiving unit 1 for receiving the reflected light of the laser light emitted from the light unit 11a toward the semiconductor wafer 1.
1b and. Then, the wafer chuck 7
The surface of the semiconductor wafer 1 is scanned while moving the laser beam in the horizontal direction, and the bend amount is measured from the change in the light receiving position of the laser light in the light receiving portion 11b accompanying the change in the reflection position of the surface of the semiconductor wafer 1 where the laser light is reflected. .

The bend amount measuring unit 11 is, for example, a CPU.
It is electrically connected to a control unit (control means) 12 configured by (Central Processing Unit), and the measured bend amount of the semiconductor wafer 1 is sent to the control unit 12. As shown in FIG. 3, the control unit 12 is also electrically connected to an input unit (input means) 13 for inputting correlation data between the bend amount of the semiconductor wafer 1 and the film thickness of the thin film to be formed, Based on this data, the control unit 12 converts the bend amount into a film thickness value. Correlation data between the bend amount and the film thickness is, for example, as shown in FIG. 4A, which shows that when the bend amount is 80 μm.
A thin film of 1000 nm is formed.

As shown in FIGS. 1, 2 and 3, in the input section 13 connected to the control section 12, the set film thickness value and film forming time of the semiconductor wafer 1, the bend amount and the film stress of the thin film ( That is, the correlation data with the stress value applied to the aluminum wiring layer or the like formed under the thin film) can be input. These numerical values are stored in a memory built in or externally attached to the control unit 12. The control unit 12 also includes a vacuum pump 16, an RF power source 6, a gas valve 17 (FIG. 3) for controlling the flow rate of the reaction gas into the reaction chamber 3, an alarm 14 for notifying an operator of an abnormal setting of the film formation time, and a bend amount. The display unit (bend amount display unit) 15a, the film thickness value display unit (film thickness value display unit) 15b, and the film stress value display unit (film stress value display unit) 15c are electrically connected to the display unit 15. .

Therefore, the control unit 12 also calculates the film stress value from the bend amount (for example, in the case shown in FIG. 4B, 7 MPa when the bend amount is 80 μm). Further, when the input film formation time elapses, the operations of the vacuum pump 16 and the RF power source 6 are stopped, and the film thickness value after film formation is compared with the set film thickness value. When the film is finished and the film thickness is equal to or less than the set film thickness value, the film formation is restarted. Further, if there is a gap between the deposited film thickness and the set film thickness value, the operator is notified by the alarm 14 that the input film deposition time is not appropriate. Then, the bend amount sent to the control unit 12,
The film thickness value and the film stress value calculated by the control unit 12 are displayed on the display unit 15.

As shown in FIG. 2, the display unit 15 is provided with a bend amount display unit 15a, a film thickness value display unit 15b, and a film stress value display unit 15c from the upper side to the lower side.
Each value is digitally displayed.
Therefore, in the case described above, the bend amount is 80μ.
m, the film thickness value is 1000 nm, and the film stress value is 7 MPa. In addition, each of the display units 15a, 15b, 15
The position of c can be set freely, and each value may be displayed in analog using a pointer-type meter.

Using the thin film forming apparatus having such a structure,
The case of forming a thin film on the semiconductor wafer 1 will be described with reference to the flowchart of FIG.

First, as a preparatory step, the wafer chuck 7
The semiconductor wafer 1 is placed on the vacuum chamber, the vacuum pump 16 evacuates the vacuum chamber 16 to keep the inside of the vacuum chamber 2 at a predetermined vacuum level while watching the pressure gauge 10, and the input unit 13 is operated to set the set film thickness value. , Film forming time, correlation data between bend amount and film thickness, and correlation data between bend amount and film stress are input.

Next, while moving the wafer chuck 7 in the horizontal direction, laser light is emitted from the light projecting section 11a of the bend amount measuring section 11 toward the semiconductor wafer 1, and the reflected light is received by the light receiving section 11b. That is, the amount of bend before film formation is measured (first step S1). This bend amount is stored in the memory. In the case of the present embodiment in which laser light is used, the bend amount is measured by scanning the surface of the semiconductor wafer 1 and determining the height difference between the outer peripheral edge and the central portion.

After that, under the condition that the reaction gas is supplied from the gas supply pipe 4, the RF power supply 6 supplies electric power of a predetermined frequency to the electrode 5. As a result, plasma of a reactive gas is generated in the reaction chamber 3, electrons are accelerated at high speed by a high frequency electric field due to high frequency discharge, ions and radicals are generated, and a thin film is formed on the semiconductor wafer 1 by a chemical reaction. (Second step S2). As described above, during the film formation, the stress applied to the semiconductor wafer 1 increases as the thin film grows, and the warp gradually increases.

The film formation is stopped after the input film formation time has elapsed (third step S3). Then, the bend amount measuring unit 11 measures the bend amount after the film formation, and the control unit 12 calculates the bend amount during the film formation from this value, and based on the correlation data between the bend amount and the film thickness input in advance. The bend amount is converted into a film thickness value of the thin film (fourth step S4).

Thereafter, the controller 12 determines whether or not the film thickness value of the formed semiconductor wafer 1 has reached the set film thickness value (fifth step S5). When it is determined that the calculated film thickness value has reached the set film thickness value read from the memory, the control unit 12 stops the operation of the vacuum pump 16 and the RF power source 6, and the gas valve 17 is closed. Thus, the film formation is completed (sixth step S6), and the process proceeds to the next sequence. On the other hand, when it is determined that the set film thickness value has not been reached, film formation is continued until the film thickness value is reached. In this case, since the actual film formation time is out of the input film formation time, in order to inform the operator of that fact and to input the appropriate film formation time again. Then, an alarm 14, for example an alarm lamp, is activated. Note that other alarms such as an alarm buzzer can be used as the alarm 14, and it is also possible to use these in combination.

Then, as described above, the semiconductor wafer 1
The bend amount, film thickness value and film stress value of are displayed on the display unit 15. Thereby, the operator can know an appropriate film formation time at the time of re-inputting, and can manage the film quality of the thin film formed on the semiconductor wafer 1.

As described above, according to the thin film forming apparatus of the present embodiment, the bend amount at the time of film formation is measured by the bend amount measuring unit 11 and the thin film formed on the semiconductor wafer 1 is back-calculated from this bend amount. Since the film thickness value is calculated, it is affected by the different deposition rate depending on whether the substrate is a silicon substrate or an oxide film substrate, the type of the semiconductor wafer 1, and the adhesion between the semiconductor wafer 1 and the wafer chuck 7. It is possible to stably form a thin film having a desired film thickness on the semiconductor wafer 1 without the need for the process.

Further, since the film forming process of the thin film forming apparatus in this embodiment is controlled by the controller 12, the thin film controlled to a predetermined film thickness can be automatically formed with almost no operator's hand. Can be formed.

Although the invention made by the present inventor has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, the control unit 12 is provided with only the function of calculating the film thickness value, and the film thickness value calculated by the control unit 12 is observed on the film thickness value display unit 15b to form a thin film having a desired thickness. It may be formed.

The thin film formed on the semiconductor wafer 1 is not limited to the above-mentioned single crystal silicon or the like, but may be amorphous silicon, silicon nitride (Si ₃ N ₄ ), phosphorus glass (PSG), Of course, various thin films such as phosphorous boron glass (BPSG) and tungsten (W) may be used.

Further, although the thin film forming apparatus of this embodiment is a plasma CVD apparatus using plasma discharge, it can be applied not only to a CVD apparatus such as a thermal CVD apparatus or a photo CVD apparatus, but also to an atom by vapor deposition or ions. It is also possible to apply to other thin film forming apparatus such as a PVD apparatus utilizing tapping.

The bend amount of the semiconductor wafer 1 is measured by moving the wafer chuck 7 horizontally. On the contrary, the bend amount is measured while the wafer chuck 7 is fixed and the bend amount measuring unit 11 is moved. You may do it. That is, the wafer chuck 7 and the bend amount measuring unit 11
It suffices that the and can be moved relative to each other. The bend amount is measured while scanning the semiconductor wafer 1 with the laser beam, but it may be measured by other optical means, and the semiconductor wafer 1 and the wafer chuck formed by the warp of the semiconductor wafer 1 may be measured. It is also possible to obtain from the space of 7.

In this embodiment, the semiconductor wafer 1 is used as the object to be processed on which a thin film is formed, but the present invention is not limited to this, and there is film stress such as a photomask. Various types of work can be applied as long as they are plate-shaped works that are warped by the film.

[0047]

The effects obtained by the typical ones of the inventions disclosed in this application will be briefly described as follows.

(1) That is, according to the thin film forming technique of the present invention, the bend amount at the time of film formation is measured by the bend amount measuring means, and the thin film formed on the plate-like work is calculated backward from this bend amount. Since the film thickness value is calculated, it affects the deposition rate that differs for each plate-shaped work depending on whether it is a silicon substrate or an oxide film substrate, the type of plate-shaped work, and the adhesion between the plate-shaped work and the stage. Without this, it becomes possible to stably form a thin film having a desired film thickness on each plate-shaped work.

(2) Similarly, since the film thickness value is calculated from the bend amount, it is possible to measure the film thickness in-line during film formation, and compare it with the case where film thickness measurement is performed offline after film formation. Improves workability.

(3). When the thickness of the formed thin film is insufficient, the film can be formed again. Therefore, the plate-like work after the film formation has a desired film thickness. And the process yield during film formation is improved.

(4) Automatically forming a thin film controlled to have a predetermined film thickness on a plate-like work by controlling the film forming process with a control means, with little operator's hand. You can

(5). By displaying the film stress value as well, it becomes possible to control the film quality of the thin film formed on the plate-like work.

[Brief description of drawings]

FIG. 1 is a schematic view showing a thin film forming apparatus according to an embodiment of the present invention.

2 is a front view showing a display unit provided in the thin film forming apparatus of FIG.

3 is a block diagram showing a control system of the thin film forming apparatus of FIG.

4A and 4B are diagrams showing data input to an input unit of the thin film forming apparatus of FIG. 1, in which FIG. 4A shows correlation data between a bend amount and film thickness, and FIG. 4B shows a bend amount and film stress. Correlation data are shown respectively.

5 is a flow chart showing a thin film forming process by the thin film forming apparatus of FIG.

[Explanation of symbols]

 1 semiconductor wafer (plate work) 2 vacuum container 3 reaction chamber 4 gas supply pipe 5 electrode 6 high frequency power supply (RF power supply) 7 wafer chuck (stage) 8 heater 9 exhaust port 10 pressure gauge 11 bend amount measurement unit (bend amount measurement) Means) 11a Light emitting unit 11b Light receiving unit 12 Control unit (Control means) 13 Input unit (Input means) 14 Alarm 15 Display unit 15a Bend amount display unit (Bend amount display unit) 15b Film thickness value display unit (film thickness value display) Means) 15c Membrane stress value display unit (Membrane stress value display means) 16 Vacuum pump 17 Gas valve S1 First step S2 Second step S3 Third step S4 Fourth step S5 Fifth step S6 Sixth step

Claims (8)

[Claims] 1. A film of the thin film is measured by measuring a bend amount of a plate-shaped work placed on a stage to form a thin film, and converting the bend amount into a film thickness of the thin film formed on the plate-like work. A method for measuring film thickness, which comprises calculating a thickness value. 2. The bend amount of the plate-like work is a space between the stage and the plate-like work formed by a height difference between an outer peripheral end and a central portion of the plate-like work or a warp of the plate-like work. It is measured from
The film thickness measuring method described. 3. The film thickness measurement according to claim 1, wherein a bend amount of the plate-shaped work placed on the stage before film formation is measured, and a thin film is formed on the plate-shaped work for a certain period of time. By measuring the film thickness of the plate-like work after film formation by the method, while the film thickness of the plate-like work has reached a desired film thickness value, while ending the film formation and shift to the next sequence, If not, the thin film forming method is characterized in that film formation is further continued until the film thickness value is reached. 4. A thin film forming apparatus for forming a thin film on a plate-like work placed on a stage, comprising: a bend amount measuring means for measuring a bend amount of the plate-like work; and a bend amount measuring means for measuring the bend amount. A thin film formation comprising: a control means for calculating a film thickness value of the thin film from the bend amount of the plate-like work; and a film thickness display means for displaying the film thickness value calculated by the control means. apparatus. 5. A thin film forming apparatus for forming a thin film on a plate-like work placed on a stage, comprising: a set film thickness value of the plate-like work, a film forming time for the plate-like work, and a plate-like work of the plate-like work. Input means for inputting the correlation data between the bend amount and the film thickness, a bend amount measuring means for measuring the bend amount of the plate-like work, and the bend amount measuring means measured after the input film formation time has elapsed. The film thickness value of the thin film is calculated from the bend amount of the plate-like work, and when the film thickness value reaches the set film thickness value, the film formation is ended and the process is shifted to the next sequence. Is a control means for continuing film formation until the set film thickness value is reached. 6. A thin film forming apparatus for forming a thin film on a plate-like work placed on a stage, comprising: a set film thickness value of the plate-like work, a film forming time for the plate-like work, and a plate-like work of the plate-like work. Input means for inputting the correlation data between the bend amount and the film thickness, a bend amount measuring means for measuring the bend amount of the plate-like work, and the bend amount measuring means measured after the input film formation time has elapsed. The film thickness value of the thin film is calculated from the bend amount of the plate-like work, and when the film thickness value reaches the set film thickness value, the film formation is ended and the process is shifted to the next sequence. Is calculated by the control means for continuing the film formation until the set film thickness value is reached and for activating an alarm notifying the operator that the film formation time is out of the input film formation time. Thin film forming apparatus characterized by having a thickness display unit thickness value is displayed. 7. A thin film forming apparatus for forming a thin film on a plate-shaped work placed on a stage, comprising: a set film thickness value of the plate-shaped work, a film formation time for the plate-shaped work, and a plate-shaped work of the plate-shaped work. Input means for inputting the correlation data between the bend amount and the film thickness and the correlation data between the bend amount of the plate-like work and the film stress, and a bend amount measuring means for measuring the bend amount of the plate-like work, The film thickness value and the film stress value of the thin film are calculated from the bend amount of the plate-like work measured by the bend amount measuring means after the film formation time has elapsed, and when the film thickness value reaches the set film thickness value. Ends the film formation and shifts to the next sequence, but if not, continues film formation until the set film thickness value is reached and confirms that the film formation time is outside the input film formation time. Know to others Control means for activating an alarm to be activated, film thickness display means for displaying the film thickness value calculated by the control means, and film stress value display means for displaying the film stress value calculated by the control means A thin film forming apparatus comprising: 8. The bend amount measuring means determines the bend amount of the plate-like work by the height difference between the outer peripheral end and the central portion of the plate-like work, or by the warp of the plate-like work and the stage. The thin film forming apparatus according to any one of claims 4 to 7, wherein the thin film forming apparatus is measured from a space with the plate-like work.