JP2013117044A - Plasma cvd apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma CVD apparatus that makes temperature inside a workpiece surface more even.SOLUTION: The plasma CVD apparatus 1 for producing a thin film on a workpiece 30 in a chamber 10 includes: a heater 11 for heating the workpiece 30, and formed of divided heaters 11a, 11b, and 11c for adjusting the temperature of each of a plurality of divided areas of the workpiece surface; a plurality of sensors 12a, 12b, and 12c for detecting at least one of an amount of warping of the workpiece surface and a temperature of the workpiece surface; and a control unit 20 for measuring a warped area of the workpiece surface or an area with uneven temperature distribution according to the detection results of the plurality of sensors, and controlling the temperatures of the divided heaters for heating the areas to thereby adjust uneven temperature distribution inside the workpiece surface.

Description

  The present invention relates to a plasma CVD apparatus, and more particularly to a heater temperature control technique.

  In the plasma CVD (Chemical Vapor Deposition) method, a gas as a material for a thin film is fed into a furnace, and the gas is ionized by high frequency or heat. Then, the work is heated to the film forming temperature by the heater, and a thin film is formed on the surface of the heated work.

  At this time, if the workpiece is placed on a heated heater, the workpiece is warped due to a temperature difference between the workpiece and the heater. When the workpiece is warped, the contact state between the workpiece and the heater changes, so that the temperature distribution in the workpiece surface is biased. Then, since the film forming temperature changes within the work surface, the film thickness of the generated thin film varies.

  Patent Document 1 describes a technique for directly detecting the temperature of a workpiece with a temperature sensor and feeding back the directly detected temperature to control the temperature of the heater.

JP 2007-70671 A

  However, in the technique described in Patent Document 1, since there is only one temperature sensor, it is not possible to eliminate the uneven temperature distribution in the workpiece surface. Therefore, the thickness of the thin film generated on the workpiece varies. It was happening.

  In general, in order to prevent warping of the workpiece caused by the heat of the heater, a dielectric layer is provided on the sample table, a voltage is applied between the sample table and the workpiece, and the workpiece is caused by the force generated between the two. Adsorbing electrostatic chucks are used. However, there is a problem that such a mechanism is expensive.

  The present invention has been made to solve such problems, and an object thereof is to provide a plasma CVD apparatus that makes the temperature in the workpiece surface more uniform.

  The plasma CVD apparatus according to the present invention is a plasma CVD apparatus for forming a thin film on a workpiece in a chamber, and is a heater for heating the workpiece, and the temperature is adjusted for each portion obtained by dividing the workpiece surface into a plurality of regions. A split heater, a plurality of sensors for detecting at least one of the warp amount of the work surface or the temperature of the work, and a region where warpage occurs in the work surface according to the detection results of the plurality of sensors Or a control unit that measures a region where the temperature distribution is biased and adjusts the temperature of the divided heater that heats the region.

  Thereby, the temperature of a division | segmentation heater can be changed according to any one or more of the curvature amount of a workpiece | work, and the bias | inclination of temperature distribution, and the temperature in a workpiece | work surface can be adjusted.

  ADVANTAGE OF THE INVENTION According to this invention, the plasma CVD apparatus which makes temperature in a workpiece | work surface more uniform can be provided.

It is a figure which shows the outline | summary of one Example of the plasma CVD apparatus concerning embodiment. It is a figure which shows an example of the plate heater concerning embodiment. It is a figure which shows the sensor concerning Embodiment and the measuring point of each sensor. It is a flowchart which shows a part of manufacturing process of the thin film of the workpiece | work 30 concerning embodiment. It is a figure which shows the outline | summary of the workpiece | work 30 and the plate heater 11 in each step of FIG.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. When the thin film is formed on the surface of the workpiece, the plasma CVD apparatus according to the present embodiment adjusts the temperature of the plate heater for each part based on one or more measured values of the warpage amount and the surface temperature of the workpiece surface. The temperature of the work surface is more uniformly controlled.

  FIG. 1 is a diagram showing an outline of an example of the plasma CVD apparatus according to the present embodiment. The plasma CVD apparatus 1 includes a chamber 10, a plate heater 11, sensors 12 a to 12 c, a gas supply port 13, a gas introduction port 14, an electrode 15, a shower head 16, a vacuum exhaust port 19, and a control unit 20. Have The chamber 10 is evacuated through the evacuation port 19.

  The plate heater 11 heats the workpiece 30 in order to form a thin film on the workpiece 30. The plate heater 11 is divided into a plurality of regions, and each of the divided regions has divided heaters 11a to 11c whose temperature can be adjusted by the control unit 20.

  The sensors 12a to 12c measure one or more of the temperature and warpage amount of the workpiece surface. The sensors 12a to 12c measure the measurement points 31a to 31c (see FIG. 3) on the surface of the workpiece 30 positioned below each of the sensors 12a to 12c. Then, the measurement result is output to the control unit 20.

  A gas for forming a thin film is fed to the work 30 through the gas supply port 13. The gas supplied through the gas supply port 13 is supplied into the chamber 10 through the gas introduction port 14.

  The electrode 15 is an electrode that applies a high frequency to the gas in the chamber 10, is formed in a plate shape, and is attached to the upper portion of the chamber 10. In the present embodiment, a high frequency is applied between the electrode 15 and the chamber 10, and the gas inside the chamber 10 is ionized by applying the high frequency.

  The shower head 16 includes an upper plate 17 and a lower plate 18, and allows the gas supplied through the gas inlet port 14 to uniformly permeate the plane of the work 30.

  The vacuum exhaust port 19 is connected to an external compressor, and the compressor lowers the atmospheric pressure inside the chamber 10 by performing vacuum exhaust.

  The control unit 20 adjusts the temperatures of the divided heaters 11a to 11c located below the measurement points based on the measurement results of the sensors 12a to 12c.

  FIG. 2 is a diagram illustrating an example of the plate heater 11. Here, the plate heater 11 is divided into, for example, three regions, and has three divided heaters 11a to 11c therein. The temperature of each of the divided heaters 11 a to 11 c is controlled by the control unit 20. Thereby, the plate heater 11 concerning this Embodiment can adjust temperature with respect to the workpiece | work 30 for every division area | region which divided | segmented the plane of the workpiece | work 30. FIG. Note that FIG. 2 is merely an example, and other shapes may be used as long as the plate heater 11 can adjust the temperature for each region.

  FIG. 3 is a diagram illustrating the measurement points 31a to 31c of the sensors 12a to 12c. FIG. 3A is a diagram illustrating measurement points 31 a to 31 c in the surface of the work 30. When the sensors 12a to 12c measure the temperature, the surface temperatures of the measurement points 31a to 31c are measured.

  When the sensors 12 a to 12 c measure the amount of workpiece warpage, the distance from the surface of the plate heater 11 to the workpiece 30 positioned vertically above the plate heater 11 is measured. As an example, the case of the sensor 12a will be described. FIG. 3B is an enlarged view of the plate heater 11 and the workpiece 30 installed on the plate heater 11 in a cross section passing through the measurement point 31a. The sensor 12a obtains the distance from the point A on the surface of the plate heater 11 to the point B on the surface of the work 30 that is perpendicular to the point A. The control unit 20 adjusts the temperature of the divided heater 11a by determining that the warpage amount of the workpiece 30 is larger in the region including the measurement point where the distance h from the point A to the point B is larger.

  That is, when the control unit 20 determines that the warpage amount of the work 30 is biased, the control unit 20 increases the temperature of the divided heater located below the region where the warpage amount of the work 30 is determined to be larger than the other regions. Alternatively, the temperature of the divided heater located below the region where the amount of warping of the workpiece is determined to be smaller than the other regions is decreased. Thereby, the temperature distribution in the surface of the workpiece 30 is made more uniform.

  Moreover, the control part 20 receives the measurement result of each temperature from the sensors 12a-12c, and judges whether temperature distribution has a bias | inclination. When it is determined that the temperature distribution of the workpiece 30 is uneven, the temperature of the divided heater located below the region where the measured temperature of the workpiece 30 is determined to be higher than the other regions is decreased. The temperature of the divided heater located under the area where the measured temperature of the workpiece 30 is determined to be lower than the other areas is increased. Thereby, the temperature distribution in the surface of the workpiece 30 is made more uniform.

  In the present embodiment, the plasma CVD apparatus has a plate heater 11 capable of adjusting the temperature for each region obtained by dividing the work 30 into a plurality of areas, and the amount of warping of the plurality of measurement points 31a to 31c on the surface of the work 30; The temperature of the plate heater 11 is adjusted for each region by controlling the temperature of the divided heater based on one or more of the temperature measurement results. Thereby, the temperature of the workpiece | work 30 surface, ie, the film-forming temperature, can be controlled uniformly. Therefore, the thickness of the thin film formed on the workpiece surface can be made more uniform.

  Next, the manufacturing process of the thin film concerning this Embodiment is demonstrated. FIG. 4 is a flowchart showing a part of the manufacturing process of the thin film of the work 30. FIGS. 5A to 5D schematically show the work 30 and the plate heater 11 in each step of FIG. First, as shown to Fig.5 (a), the workpiece | work 30 is installed on the heated plate heater 11 (step S1). At this time, the workpiece 30 may be warped due to a temperature difference between the workpiece 30 and the plate heater 11.

  Next, as shown in FIG.5 (b), any one or more of the surface temperature of the measurement points 31a-31c and the amount of curvature is measured with the sensors 12a-12c, and it outputs to the control part 20 (step S2). . As illustrated in FIG. 5C, the control unit 20 detects a region with a large amount of warpage and a temperature distribution bias based on the measurement results received from the sensors 12a to 12c (step S3). The control unit 20 controls any one or more of the divided heaters 11a to 11c according to the warpage amount and the temperature distribution, and more uniformly controls the temperature in the surface of the workpiece 30. Then, as shown in FIG. 5D, when the temperature of the heater 11 is stabilized, a plasma 40 is generated on the work 30 by applying a high frequency to the gas supplied from the gas inlet 14 to form a film. Processing is started (step S4).

  According to the plasma CVD apparatus 1 according to the present embodiment, the temperature in the workpiece surface can be made more uniform without using an expensive mechanism such as an electrostatic chuck, and a thin film having a more uniform thickness can be formed. can do.

  It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Plasma CVD apparatus 10 Chamber 11 Plate heater 11a Division heater 11b Division heater 11c Division heater 12a Sensor 12b Sensor 12c Sensor 13 Gas supply port 14 Gas introduction port 15 Electrode 16 Shower head 17 Upper plate 18 Lower plate 19 Vacuum exhaust port 20 Control part 30 Workpiece 31a Measurement point 31b Measurement point 33c Measurement point

Claims (1)

A plasma CVD apparatus for producing a thin film on a workpiece in a chamber,
A plate heater for heating the workpiece, a divided heater capable of adjusting the temperature for each portion obtained by dividing the workpiece surface into a plurality of regions,
A plurality of sensors for detecting any one or more of the amount of warpage of the workpiece surface or the temperature of the workpiece;
According to the detection results of the plurality of sensors, a region where warpage occurs in the workpiece surface or a region where the temperature distribution is biased is measured, and the temperature of the divided heater that heats the region is controlled. And a control unit that adjusts the deviation of the temperature distribution in the workpiece surface.

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