JPH01265A - Film forming equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a film forming apparatus for forming a film on a substrate in a reduced pressure gas atmosphere.

[Prior Art] Conventionally, in a film forming apparatus that forms a film on a substrate in a reduced pressure gas atmosphere, the gas pressure control section J1, substrate temperature control section, bias voltage control section, etc. were individually controlled. ,I&
, evaluate the stress of the membrane after v has finished, 1-1
It was necessary to carefully examine the film formation conditions in order to obtain the target film stress.

[Problems to be Solved by the Invention] Incidentally, if warpage occurs on the substrate during semiconductor film formation, it causes problems during patterning, and further causes problems such as film peeling and cracks. Furthermore, when forming a film of a magnetic material, the magnetic properties are affected by the stress of the film.

Warpage of the substrate caused by stress in the film during film formation is caused by, for example,
When forming a film of a magnetic material using sendust, the temperature varies depending on the gas pressure during film formation (FIG. 5), the substrate temperature (FIG. 6), and the bias voltage applied to the substrate (FIG. 7).

However, in the conventional example described above, in order to obtain the target film stress, it is necessary to carefully examine the film forming conditions such as R & gas pressure during film formation, substrate temperature, and bias voltage applied to the substrate. If the target stress was not obtained, there were problems such as the produced film being wasted.

[Means for Solving the Problems] The T&& apparatus according to the present invention is capable of forming a film on a substrate in a reduced pressure gas atmosphere! Iei
? Z is characterized by comprising a film stress detection means for detecting the stress of the substrate, and a film formation strip side control means for controlling film formation conditions based on the detection result.

[Function] According to the present invention, by providing a film-forming condition control means that detects the stress of the film during film-forming using a film-stress detecting means including a sensor and controls the film-forming conditions based on the detection result, the film-forming process can be carried out. The stress of the membrane inside can be controlled to a target value.

' [Embodiment] FIG. 1 is a schematic diagram showing an embodiment of a film forming apparatus according to the present invention.

In the figure, a chamber 1 is connected to a gas pump 3 via a gas introduction valve 2 that adjusts the pressure of gas during film formation, and is also connected to an exhaust system W15 via an exhaust valve 4.

A conductive substrate holder 7 is provided within the chamber 1 via an insulator 6, and a substrate 8 is fixed to this substrate holder 7. On the r side of the holder 7, a film forming material 9 is placed on the holder 10 facing the substrate 8, and inside the holder 7, a substrate heater 11 and a stress sensor 12- are placed. ing.

The stress sensor 12 has a stylus-type probe 13 on the surface 8b of the substrate 8 opposite to the film-forming surface 8a, and detects the warping of the substrate 8 caused by film stress as the film is formed, and detects the warping value. is converted into stress.

A film forming apparatus having such a configuration has a film forming condition control section 2.
Controlled by 0.

The film forming condition control unit 20 receives a signal from the film stress detection unit 21 and includes a gas pressure control unit 22 that controls the gas introduction valve 2;
A substrate temperature controller 23 that controls the substrate heater 11 and a bias voltage controller 24 that applies a bias voltage to the substrate holder 7 are controlled to control the stress of the film being formed to match a target value. The membrane stress detection unit 21 compares the stress detected by the stress sensor 12 with a target stress, and outputs the comparison result.

Next, the operation of this embodiment will be explained with reference to the flowchart shown in FIG.

First, the exhaust valve 4 is opened, and the pressure inside the chamber 1 is reduced using the exhaust device 5.

Next, the gas in the gas cylinder 3 is introduced into the chamber 1 by controlling the gas introduction valve 2 by the gas control unit 22 so that the gas pressure PG in the chamber 1 becomes the initial pressure PCO. Further, the substrate temperature controller 23 controls the substrate heater 11 so that the substrate temperature TS becomes the initial setting temperature T So , and the bias voltage controller 24 controls the substrate heater 11 so that the bias voltage vS becomes the initial voltage VSo. A bias voltage is applied to the substrate 8 through the holder 7 (step 30).

When the initial setting conditions are satisfied in this way, the film-forming material 9 held in the holder 10 is released and the film-forming surface 8a of the plate 8 is
A film is formed on top (step 31).

As the film is formed on the substrate 8, the stress δ of the film causes the substrate 8 to warp, and the state of this warp is detected by the stress sensor 1.
2, and the WJ stress detection unit 21 compares the target film stress δ0 with the actual film stress δ (step 32).

If the actual film stress δ does not match the target film stress δ0, the condition in step 32 becomes NO, and the film stress detection unit 21 issues a command to change the film forming conditions so that the two match. It is output to the condition control section 20. The film-forming condition control unit 20 that received the command issues film-forming condition commands to the gas pressure control unit 22, substrate temperature control unit 23, and bias voltage control unit 24, respectively, so that the stress δ during film formation is equal to the set stress δ0. The substrate temperature TS, bias voltage vS, and gas pressure PG are changed within allowable ranges in the same direction (step 33).

The operations of steps 31 and 32 are then repeated.

If the actual film stress δ matches the target film stress δG, the thicknesses are compared (step 34).

If the thickness has not reached the target value, steps 31 to 33 described above are repeated, and when the target value is reached, the apparatus stops (step 35).

As described above, by providing the film stress sensor 12, the film stress detection unit 21, and the film forming condition control unit 2o, the I
& The stress of the film during film formation can be controlled to the target level.

FIG. 3 shows another embodiment of the stress sensor 12, in which a mirror part 40 is provided at a position offset from the center of the surface 8b of the substrate 8, and the light emitted from the laser oscillator 41 is reflected by this mirror part 40. The sensor 42 is configured to receive the reflected laser light.

According to such a configuration, when the substrate 8 warps due to the stress of the deposited film, the mirror portion 40 is tilted, so that the laser beam reflected by the mirror portion 40 is directed to the sensor 4.
2 Move above. This movement is detected by a sensor 42 and converted into membrane stress.

Depending on the type of substrate, a portion of the mirror may be omitted and the substrate may be used directly as a portion of the mirror.Also, if the film forming conditions permit, a laser oscillator and an optical sensor may be provided on the film forming surface side of the substrate. The formed film may be used as a part of the mirror.

FIG. 4 shows still another embodiment of the stress sensor 12, in which a pair of electrodes 50 and 51 are provided on the base 8b of the substrate 8, and
When a film is formed on the substrate 8 and the substrate 8 warps due to the stress of the film, the position of the electrode 50 is shifted and the capacitance between the electrodes 50 and 51 changes. Therefore, this variation can be detected by the capacitance meter 52 and converted into film stress.

[Effects of the Invention] As explained in detail below, according to the present invention, the film forming conditions are controlled based on the film stress detection means including a sensor for detecting the stress of the film during film formation and the result of the film stress detection. By providing a film-forming condition control means to control the film-forming conditions, there is no need to carefully examine film-forming conditions such as gas pressure, substrate temperature, and bias voltage applied to the substrate during film-forming, and there is no need to perform unnecessary film-forming. , it becomes possible to control the stress of the film during film formation to a target value.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing an embodiment of a film forming apparatus according to the present invention, FIG. 2 is a flowchart for explaining the operation of the embodiment shown in FIG. 1, and FIG. 3 is a stress sensor FIG. 2 is a configuration diagram showing another embodiment of the . FIG. 4 is a configuration diagram showing still another embodiment of the stress sensor. FIG. 5 is a characteristic diagram showing the relationship between substrate warpage and gas pressure. FIG. 6 is a diagram showing the relationship between substrate warpage and substrate temperature. FIG. 7 is a characteristic diagram showing the relationship between substrate warpage and bias voltage applied to the substrate. 1... Chamber 2... Gas introduction pulp 7, ψ, substrate holder 811 ・ ・ ノ, ti Plate 11... Thumb plate heater 12... Stress sensor 20, Control film forming condition control unit 21・Membrane stress detection unit 22 ・Gas pressure control unit 23 ・Substrate temperature control unit 24 ・Bias voltage control unit Agent Patent attorney Enpei Yamashita Figure 2

Claims (2)

[Claims] (1) A film forming apparatus for forming a film on a substrate, comprising a film stress detecting means for detecting the stress of the substrate, and a film forming condition control means for controlling the film forming conditions based on the detection result. A film forming apparatus characterized by: (2) The film forming apparatus according to claim 1, wherein the film forming conditions are gas pressure, substrate temperature, and bias voltage applied to the substrate.