JP2016174121A - Method of manufacturing semiconductor device, film formation device, and cmp device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor device capable of controlling a film thickness to such a value that variation in transmissivity of light can be suppressed.SOLUTION: A method of manufacturing a semiconductor device includes the steps of: (a) forming a photodiode 17 on a semiconductor wafer 15; (b) forming a film on the photodiode, irradiating the photodiode with light via the film, measuring current generated at the photodiode, and repeatedly performing the film formation and the measurement; (c) deciding a timing when the film formation is terminated on the basis of a result of the measurement; and (d) terminating the film formation at the timing decided at the step (c).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a semiconductor device manufacturing method, a film forming apparatus, and a CMP apparatus.

  FIG. 5 is a diagram schematically showing the relationship between the film thickness of a film (film serving as an optical path to the photodiode) formed on the photodiode and the light transmittance of the film.

  The optical characteristics (such as light deviation) of the photodiode are very sensitive to variations in the thickness of the film (interlayer film or protective film) serving as an optical path. The reason is that the light transmittance varies as the film thickness of the optical path film varies. And, the variation in film thickness of the optical path film is a major factor in characteristic deviation and yield reduction.

  Specifically, as shown in FIG. 5, the transmittance of the film serving as the optical path has a periodic dependence on the film thickness. For this reason, in order to suppress the influence on the film thickness variation as much as possible and to obtain a stable characteristic (yield), it is important to adjust the film thickness so that the film has a peak or valley film thickness of the periodic curve.

  However, in many cases, the film serving as the optical path has a wide variety of laminated structures, and there is a variation in film thickness for each layer, and this periodic curve is affected by the film thickness (variation) of each layer and fluctuates.

  Further, since this periodic curve also changes depending on the wavelength of the target light source, as shown in FIG. 6, when there are a plurality of light sources having different wavelengths (eg, Red / Green / Blue), each has an independent periodic curve. Draw. Furthermore, there are film thickness variations between wafers and within the wafer surface.

On the other hand, Patent Document 1 discloses that the film thickness is controlled by measuring optical characteristics of a multilayer film in advance using a monitor substrate.
However, for many of the above-mentioned variation factors, film thickness adjustment by conventional monitors and simulations, etc. should be adjusted to a film thickness suitable for the optical characteristics and stably mass-produced with good yield. Is very difficult.

  In other words, even if the optical characteristics of the multilayer film are measured using a monitor substrate in advance, the optical characteristics of the film are not directly measured at the time of film formation or polishing, so the light transmittance varies. It is difficult to sufficiently control the film thickness for various factors.

JP 7-34247 A

Some aspects of the present invention provide a method for manufacturing a semiconductor device in which the optical characteristics of a film are directly measured during film formation or polishing, thereby controlling the film thickness so that fluctuations in light transmittance can be suppressed. Related.
In addition, some aspects of the present invention relate to a film forming apparatus that can directly measure the optical characteristics of a film when the film is formed.
Some aspects of the invention also relate to a CMP apparatus that can directly measure the optical properties of the film during polishing of the film.

  One embodiment of the present invention includes a step (a) of forming a photodiode on a semiconductor wafer, forming a film on the photodiode, irradiating the photodiode with light through the film, and generating the photodiode. A step (b) of measuring current and repeating the film formation and the measurement, a step (c) of deciding when to end the film formation based on a result of the measurement, and a step (c). And a step (d) of terminating the film formation at another time.

  According to the above-described aspect of the present invention, the optical characteristics of the film are directly measured at the time of film formation, and the timing of film formation is determined based on the measurement result. It is possible to control the film thickness to be possible.

  One embodiment of the present invention includes a step (a) of forming a photodiode on a semiconductor wafer, a step (b1) of forming a film over the photodiode, a portion of the film is polished by CMP, and the photo Irradiating the diode with light through the film, measuring a current generated in the photodiode, repeating the polishing and the measurement (b), and determining the timing of the polishing based on the measurement result A method of manufacturing a semiconductor device, comprising: a step (c); and a step (d) for terminating the polishing at a time determined in the step (c).

  According to the one aspect of the present invention, the optical characteristics of the film are directly measured at the time of polishing the film, and the time for ending the polishing is determined based on the measurement result. The thickness can be controlled.

  In one embodiment of the present invention, in the above embodiment of the present invention, the step (b) includes a step of calculating the light transmittance of the film from a current value obtained by measuring a current generated in the photodiode. A method for manufacturing a semiconductor device, comprising: Thereby, it is possible to easily determine the time to end the film formation or polishing based on the measurement result of the optical characteristics.

  One embodiment of the present invention is the above-described embodiment of the present invention, wherein the time of the step (c) is a time when the result of the measurement falls within a desired current value range. A method for manufacturing a semiconductor device. Thereby, it is possible to easily determine the time to end the film formation or polishing based on the measurement result of the optical characteristics.

  In one embodiment of the present invention, measuring the current generated in the photodiode in the step (b) is electrically connected to the photodiode, and is connected to an electrode pad formed on the semiconductor wafer. A method for manufacturing a semiconductor device, comprising: contacting a prober; and measuring a current generated by light received by the photodiode by the measuring instrument. Thereby, the measurement of an optical characteristic can be performed reliably.

  Further, according to one embodiment of the present invention, in the above embodiment of the present invention, the current generated in the photodiode in the step (b) is electrically connected to the photodiode, and is measured on the semiconductor wafer. A prober of a measuring instrument is brought into contact with the electrode pad formed on the electrode, and a current generated by light received by the photodiode is measured by the measuring instrument, and the film formation in the step (b) A method of manufacturing a semiconductor device, comprising forming the film while covering a pad with a cover.

  According to one embodiment of the present invention, the film is formed while the electrode pad is covered with the cover, so that the film can be suppressed from being formed on the electrode pad.

  In one embodiment of the present invention, in the above embodiment of the present invention, the light applied to the photodiode in the step (b) is light having a plurality of wavelengths. It is. Thereby, it becomes possible to make the film thickness suitable for a plurality of wavelengths.

  One embodiment of the present invention includes a film formation mechanism for forming a film, a light source, a measuring instrument including a prober, and a control unit. The control unit forms a film with the film formation mechanism, and An optical characteristic is measured by a light source and the measuring instrument, and the film forming mechanism is controlled based on the measurement result.

  According to one embodiment of the present invention, since the light source and the measuring instrument are provided, the optical characteristics of the film can be directly measured when the film is formed.

  One embodiment of the present invention is the above embodiment of the present invention, wherein the control unit forms a film over the photodiode of the semiconductor wafer by the film formation mechanism, and passes the film through the photodiode by the light source. Irradiate light, measure the current generated in the photodiode by the measuring instrument, control to repeat the film formation and the measurement, determine the time to end the film formation based on the measurement result, The film forming apparatus is characterized in that the film forming mechanism is controlled so as to finish the film forming at a time. As a result, the optical characteristics of the film can be measured directly at the time of film formation, and the timing for ending the film formation can be determined based on the measurement result. As a result, the film can suppress fluctuations in light transmittance. The thickness can be controlled.

  According to another aspect of the present invention, in the above aspect of the present invention, the current generated in the photodiode is measured by electrically connecting the photodiode to the electrode pad formed on the semiconductor wafer. The prober is brought into contact with the probe, and a current generated by the light received by the photodiode is measured by the measuring instrument, and has a cover that covers the electrode pad when the film is formed by the film forming mechanism. Is a film forming apparatus.

  According to the one aspect of the present invention, since the cover for covering the electrode pad is provided, the formation of a film on the electrode pad can be suppressed.

  Further, according to one embodiment of the present invention, in the one embodiment of the present invention, the film formation mechanism includes a film formation source having a shower head having a smaller diameter than the semiconductor wafer, and a rotation mechanism that rotates the shower head. Is a film forming apparatus characterized by This makes it easy to repeat the film formation and the measurement of optical characteristics.

  One embodiment of the present invention includes a polishing mechanism for polishing a film by CMP, a light source, a measuring instrument including a prober, and a control unit, wherein the control unit polishes the film by the polishing mechanism, A CMP apparatus is characterized in that optical characteristics are measured by a light source and the measuring instrument, and the polishing mechanism is controlled based on the measurement result.

  According to the above aspect of the present invention, since the light source and the measuring instrument are provided, the optical characteristics of the film can be directly measured when the film is polished.

  One embodiment of the present invention is the above-described embodiment of the present invention, wherein the control unit polishes a film formed on the photodiode of the semiconductor wafer by the polishing mechanism, and the light source supplies the photodiode to the photodiode. Irradiate light through the film, measure the current generated in the photodiode by the measuring instrument, control to repeat the polishing and the measurement, determine the time to end the polishing based on the measurement results, The CMP apparatus is characterized in that the polishing mechanism is controlled so as to finish the polishing at a time. As a result, it is possible to measure the optical characteristics of the film directly at the time of polishing the film, and to determine when to finish the polishing based on the measurement result. As a result, the film thickness can suppress fluctuations in light transmittance. It becomes possible to control.

  According to another aspect of the present invention, in the above aspect of the present invention, the current generated in the photodiode is measured by electrically connecting the photodiode to the electrode pad formed on the semiconductor wafer. The CMP apparatus is characterized in that the prober is brought into contact with the probe and the current generated by the light received by the photodiode is measured by the measuring instrument. Thereby, the measurement of an optical characteristic can be performed reliably.

(A) is a cross-sectional view schematically showing a film formation apparatus according to one embodiment of the present invention, (B) is a cross-sectional view for explaining the measurement of optical characteristics of the film formation apparatus shown in (A), (C ) Is a schematic plan view of the film forming apparatus shown in FIG. (A) is a plan view of the semiconductor wafer shown in FIG. 1, (B) is a cross-sectional view showing a photodiode for monitoring and an optical path film, and (C) is a cross-sectional view showing a photodiode for product and an optical path film. The correlation figure of the optical path film thickness to the photodiode for the film thickness adjustment by monitor measurement, and the transmittance | permeability of the light of several wavelengths. FIG. 4A is a cross-sectional view schematically showing a CMP apparatus according to one embodiment of the present invention, and FIG. 4B is a cross-sectional view for explaining the measurement of optical characteristics of the CMP apparatus shown in FIG. The correlation figure of the optical path film thickness to a photodiode, and the light transmittance. The correlation diagram of the optical path film thickness to a photodiode, and the transmittance | permeability of each light of red, green, and blue.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below.

[Embodiment 1]
FIG. 1A is a cross-sectional view schematically illustrating a film formation apparatus according to one embodiment of the present invention, and is a diagram for describing a state during film formation. FIG. 1B is a cross-sectional view for explaining measurement of optical characteristics of the film formation apparatus illustrated in FIG. FIG. 1C is a schematic plan view of the film formation apparatus illustrated in FIG. 2A is a plan view of the semiconductor wafer shown in FIG. 1, and FIG. 2B is a cross-sectional view showing a monitoring photodiode and an optical path film. FIG. 2C is a cross-sectional view showing a product photodiode and an optical path film. The configuration of the product photodiode and optical path film is the same as that of the monitor photodiode and optical path film.

First, the structure of the film forming apparatus will be described.
The film forming apparatus shown in FIG. 1 includes a film forming mechanism having a shower head 11, a light source 12, a measuring instrument 14 provided with a prober 13, and a control unit (not shown). The control unit forms a film with the film forming mechanism, measures optical characteristics with the light source 12 and the measuring instrument 14, and controls the film forming mechanism based on the measurement result.

  The film forming mechanism is disposed on the shower head 11 and has a film forming source (not shown) for generating plasma in the film forming source gas and a rotating mechanism for rotating the shower head 11 as shown by an arrow 16. Plasma is generated in the film forming source gas by the film forming source, and the film forming particles fall on the semiconductor wafer 15 from the shower head 11, thereby forming films on the monitor and product photodiodes. The diameter of the shower head 11 is preferably smaller than the diameter of the semiconductor wafer 15, for example, about ½ of the diameter of the semiconductor wafer 15.

  The light emitted from the light source 12 to the monitoring photodiode (also referred to as the second photodiode) 17 of the monitoring optical device of the semiconductor wafer 15 may be a single wavelength light or a plurality of wavelengths of light. There may be.

  The measuring instrument 14 measures the current generated by the light received by the monitoring photodiode 17 by bringing the prober 13 into contact with the electrode pad 19 electrically connected to the monitoring photodiode 17.

  The film forming apparatus includes a stage 20 on which the semiconductor wafer 15 is placed, and a cover 41 attached to the stage 20. The cover 41 covers the electrode pad 19. When the film is formed on the electrode pad 19 when the film is formed by the film forming mechanism, the prober 13 can be brought into electrical contact with the electrode pad 19. This is to prevent this. The stage 20, the cover 41, and the shower head 11 are disposed in a vacuum chamber (not shown).

  The control unit controls as follows. A film is formed on the product photodiode (also referred to as the first photodiode) 17a of the product optical device 21 on the semiconductor wafer 15 and the monitor photodiode 17 of the monitor optical device by the film formation mechanism. To do. The product photodiode 17a is formed in the product optical device 21 shown in FIG. Next, when the shower head 11 is not positioned above the monitor photodiode 17, the light source 12 irradiates the monitor photodiode 17 with light through the film, and the measuring instrument 14 measures the current generated in the monitor photodiode 17. . When the shower head 11 is positioned above the monitoring photodiode 17, the light emitted from the light source 12 is blocked by the shower head 11. Next, the film formation and the measurement are repeated. Then, a time for ending the film formation is determined based on the measurement result, and the film formation mechanism is controlled so as to end the film formation at that time.

Next, a method for manufacturing a semiconductor device will be described.
As shown in FIG. 2, the product photodiode 17 a of the product optical device 21 and the monitor photodiode 17 of the monitor optical device are formed on the silicon substrate 24 of the semiconductor wafer 15. The product photodiode 17 a has the same structure as the monitor photodiode 17. Next, an electrode pad 19 electrically connected to the monitoring photodiode 17 is formed on the semiconductor wafer 15.

  Next, the semiconductor wafer 15 is placed on the stage 20 of the film forming apparatus shown in FIG. Next, an interlayer insulating film 22 such as a silicon oxide film shown in FIG. 2B is formed on the product photodiode 17 a and the monitor photodiode 17 of the semiconductor wafer 15. Specifically, as shown in FIG. 1A, plasma is generated in a film forming source gas by a film forming source while rotating the shower head 11 as indicated by an arrow 16, and film forming particles are transferred from the shower head 11 to the semiconductor wafer. Pour down 15 Thus, the interlayer insulating film 22 is formed on the monitoring photodiode 17 and the product photodiode 17a. This film formation is performed while covering the electrode pad 19 with the cover 41. For this reason, the interlayer insulating film 22 is not formed on the electrode pad 19.

  Next, as shown in FIG. 1B, when the shower head 11 is not positioned above the monitoring photodiode 17, the light source 12 irradiates the monitoring photodiode 17 with light through the interlayer insulating film 22, and the measuring instrument 14. To measure the current generated in the monitoring photodiode 17. Specifically, the prober 13 of the measuring instrument 14 is brought into contact with the electrode pad 19 and the current generated by the light received by the monitoring photodiode 17 is measured by the measuring instrument 14.

  The formation of the interlayer insulating film 22 and the measurement of current are repeated. Then, based on the result of the measurement, the timing for ending the formation of the interlayer insulating film 22 is determined. The timing may be, for example, when the current measurement result falls within a desired current value range. In addition, the light transmittance of the interlayer insulating film may be calculated from the current value obtained by measuring the current generated in the monitoring photodiode 17, and in this case, when the film formation is completed, the calculated result is a desired transmittance. The time may be within the range. Note that the range of the desired current value has the same meaning as the range of the desired transmittance.

  Next, the film formation of the interlayer insulating film 22 is terminated at the predetermined time. Next, the semiconductor wafer 15 is removed from the stage 20. Next, a step of forming a connection hole in the interlayer insulating film 22, a step of embedding a W plug in the connection hole, a step of forming a wiring on the interlayer insulating film 22, a step of forming an interlayer insulating film on the wiring, the interlayer A process of polishing the insulating film by CMP (Chemical Mechanical Polishing) is performed (not shown).

  Thereafter, the semiconductor wafer 15 is placed on the stage 20 of the film forming apparatus shown in FIG. Next, a protective film 23 such as a silicon nitride film shown in FIGS. 2B and 2C is formed on the interlayer insulating film 22 of the semiconductor wafer 15. Specifically, as shown in FIG. 1A, plasma is generated in a film forming source gas by a film forming source while rotating the shower head 11 as indicated by an arrow 16, and film forming particles are transferred from the shower head 11 to the semiconductor wafer. Pour down 15 Thereby, the protective film 23 is formed on the interlayer insulating film 22. The film forming source gas at this time is different from the film forming source gas used when forming the interlayer insulating film. The protective film 23 is formed while the electrode pad 19 is covered with the cover 41. For this reason, the protective film 23 is not formed on the electrode pad 19.

  Next, as shown in FIG. 1B, when the shower head 11 is not positioned above the monitor photodiode 17, the light source 12 irradiates the monitor photodiode 17 with light through the protective film 23 and the interlayer insulating film 22. The current generated in the monitoring photodiode 17 is measured by the measuring instrument 14. Specifically, the prober 13 of the measuring instrument 14 is brought into contact with the electrode pad 19 and the current generated by the light received by the monitoring photodiode 17 is measured by the measuring instrument 14.

  The formation of the protective film 23 and the measurement of current are repeated. Then, based on the result of the measurement, the timing for ending the formation of the protective film 23 is determined. The timing may be, for example, when the current measurement result falls within a desired current value range. In addition, the light transmittance of the protective film 23 and the interlayer insulating film 22 may be calculated from the current value obtained by measuring the current generated in the monitoring photodiode 17. May be within the desired transmittance range.

  Next, the formation of the protective film 23 is terminated at the predetermined time. Next, the semiconductor wafer 15 is removed from the stage 20.

  According to the present embodiment, the optical characteristics of the film are directly measured when the interlayer insulating film 22 is formed or the protective film 23 is formed, and the measurement result is fed back to the film forming process. This makes it possible to control the interlayer insulating film 22 serving as the optical path film or the laminated film of the interlayer insulating film 22 and the protective film 23 to a film thickness that can suppress fluctuations in light transmittance. It becomes possible to adjust to a suitable film thickness. In other words, in an optical device having a photodiode, it is possible to cancel a film thickness variation for each layer, a difference due to a light source wavelength, and a film thickness variation between semiconductor wafers in a laminated film serving as an optical path.

  In the method of manufacturing a semiconductor device according to the present embodiment, measurement is performed by irradiating the monitor photodiode 17 with light having one wavelength from one light source 12, but the present invention is not limited to this. When manufacturing optical devices for products with multiple light source wavelengths on a semiconductor wafer, it is suitable for each wavelength by preparing multiple light sources for irradiating the monitor photodiode and monitoring light of multiple wavelengths It is possible to make the film thickness. For example, as shown in FIG. 3, it is suitable for optical characteristics and yield by aligning the phase with the wavelength of each light source of red, green, and blue and controlling the film thickness at the peak or valley. It is possible to adjust the film thickness.

  In this embodiment, the film is formed and the optical characteristics are measured in the same vacuum chamber. However, the optical characteristics may be measured in a vacuum chamber different from the vacuum chamber in which the film is formed. Good. In this case, the vacuum chamber for film formation and the vacuum chamber for measuring optical characteristics are preferably connected, and the vacuum chamber for measuring optical characteristics may be a pre-chamber of the vacuum chamber for film formation.

[Embodiment 2]
FIG. 4A is a cross-sectional view schematically illustrating a CMP apparatus according to one embodiment of the present invention, and is a diagram for describing a state during polishing. FIG. 4B is a cross-sectional view for explaining the measurement of the optical characteristics of the CMP apparatus shown in FIG.

First, the structure of the CMP apparatus will be described.
The CMP apparatus shown in FIG. 4 includes a polishing mechanism for polishing a film by CMP, a light source 32, a measuring instrument 34 provided with a prober 33, and a control unit (not shown). This control part polishes a film | membrane with a grinding | polishing mechanism, measures an optical characteristic with the light source 32 and the said measuring device 34, and controls a grinding | polishing mechanism based on the measurement result.

  The polishing mechanism includes a stage 40 provided with a polishing pad (not shown), a polishing head 30 that holds the semiconductor wafer 15, a rotating mechanism that rotates the polishing head 30 as indicated by an arrow 36, and supplies slurry to the polishing pad. A slurry supply mechanism (not shown). The semiconductor wafer 15 is held on the polishing head 30, the slurry is supplied to the polishing pad by the slurry supply mechanism, and the polishing head 30 is rotated as indicated by an arrow 36 while pressing the semiconductor wafer 15 against the polishing pad to perform CMP polishing.

  The light emitted from the light source 32 to the monitoring photodiode (also referred to as a second photodiode) 17 of the monitoring optical device of the semiconductor wafer 15 may be a single wavelength light or a plurality of wavelengths of light. There may be.

  The measuring instrument 34 measures the current generated by the light received by the monitoring photodiode 17 by bringing the prober 33 into contact with the electrode pad 19 electrically connected to the monitoring photodiode 17.

  The control unit controls as follows. 2B and FIG. 2C formed on the product photodiode (also referred to as a first photodiode) 17a of the product optical device 21 on the semiconductor wafer 15 and the monitor photodiode 17. 22 is polished by a polishing mechanism. Next, the polishing head 30 is moved to a position facing the light source 32, the light is irradiated to the monitoring photodiode 17 through the interlayer insulating film 22, and the current generated in the monitoring photodiode 17 is measured by the measuring instrument 34. To do. Next, the film formation and the measurement are repeated. Then, the timing for ending the polishing is determined based on the measurement result, and the polishing mechanism is controlled so as to end the polishing at that timing.

Next, a method for manufacturing a semiconductor device will be described.
As in the first embodiment, as shown in FIG. 2, the product photodiode 17a of the product optical device 21 and the monitor photodiode 17 of the monitor optical device are formed on the silicon substrate 24 of the semiconductor wafer 15. Next, an electrode pad 19 electrically connected to the monitoring photodiode 17 is formed on the semiconductor wafer 15.

  Next, an insulating film is formed on the product photodiode 17a and the monitor photodiode 17 of the semiconductor wafer 15, and wiring is formed on the insulating film. Next, an interlayer insulating film 22 such as a silicon oxide film is formed over the wiring and the insulating film by the same method as in the first embodiment. It is assumed that the interlayer insulating film 22 is not formed on the electrode pad 19.

  Next, the semiconductor wafer 15 is held on the polishing head 30 of the CMP apparatus shown in FIG. Next, a part of the interlayer insulating film 22 of the semiconductor wafer 15 is polished by CMP. Specifically, as shown in FIG. 4A, the slurry is supplied to the polishing pad by the slurry supply mechanism, and the polishing head 30 is rotated as indicated by an arrow 36 while pressing the semiconductor wafer 15 against the polishing pad. Thereby, the interlayer insulating film 22 is polished.

  Next, as shown in FIG. 4B, the polishing head 30 is moved to a position facing the light source 32. Next, light is irradiated to the monitoring photodiode 17 through the interlayer insulating film 22 by the light source 32, and the current generated in the monitoring photodiode 17 is measured by the measuring instrument 34. Specifically, the prober 33 of the measuring instrument 34 is brought into contact with the electrode pad 19, and the current generated by the light received by the monitoring photodiode 17 is measured by the measuring instrument 34.

  The polishing of the interlayer insulating film 22 and the current measurement are repeated. Then, based on the result of the measurement, the timing for finishing the polishing of the interlayer insulating film 22 is determined. The timing may be, for example, when the current measurement result falls within a desired current value range. In addition, the light transmittance of the interlayer insulating film may be calculated from the current value obtained by measuring the current generated in the monitoring photodiode 17, and in this case, when the film formation is completed, the calculated result is a desired transmittance. The time may be within the range. Note that the range of the desired current value has the same meaning as the range of the desired transmittance.

  Next, the polishing of the interlayer insulating film 22 is terminated at the predetermined time. Next, the semiconductor wafer 15 is removed from the polishing head 30. Next, a protective film 23 is formed on the interlayer insulating film 22 by the same method as in the first embodiment.

  According to the present embodiment, the optical characteristic of the film is directly measured at the time of polishing the interlayer insulating film 22, and the measurement result is fed back to the polishing process. As a result, the interlayer insulating film 22 serving as the optical path film can be controlled to a film thickness that can suppress fluctuations in light transmittance, and can be adjusted to a film thickness suitable for optical characteristics and yield. . In other words, in an optical device having a photodiode, it is possible to cancel a film thickness variation for each layer, a difference due to a light source wavelength, and a film thickness variation between semiconductor wafers in a laminated film serving as an optical path.

  In the method of manufacturing a semiconductor device according to the present embodiment, measurement is performed by irradiating light of one wavelength from one light source 12 to the monitoring photodiode 17, as in the first embodiment. It is not limited.

In one embodiment of the present invention, when a specific B (hereinafter referred to as “B”) is formed above (or below) a specific A (hereinafter referred to as “A”) (B is formed), It is not limited to the case where B is directly formed (or B is formed) on (or below). It includes the case where B is formed (otherwise B) is formed on the upper side (or the lower side) of A through other things as long as the effects of the present invention are not inhibited.
Further, the structure expressed by the expression above (or below) is not necessarily limited to one direction. For example, when B is formed above (or below) A (B is formed), the semiconductor device When used upside down, it includes the case where B is formed below (or above) A (B is formed).

  DESCRIPTION OF SYMBOLS 11 ... Shower head, 12 ... Light source, 13 ... Prober, 14 ... Measuring instrument, 15 ... Semiconductor wafer, 16 ... Arrow, 17 ... Monitor photodiode (also called 2nd photodiode), 17a ... Product photodiode ( 19 ... electrode pad, 20 ... stage, 21 ... product optical device, 22 ... interlayer insulating film, 23 ... protective film, 24 ... silicon substrate, 30 ... polishing head, 32 ... light source, 33 ... Prober, 34 ... Measuring instrument, 40 ... Stage, 41 ... Cover.

Claims (14)

Forming a photodiode on a semiconductor wafer (a);
(B) forming a film on the photodiode, irradiating the photodiode with light through the film, measuring a current generated in the photodiode, and repeating the film formation and the measurement;
A step (c) of determining a time to end the film formation based on the result of the measurement;
And (d) ending the film formation at a time determined in the step (c). Forming a photodiode on a semiconductor wafer (a);
A step (b1) of forming a film on the photodiode;
(B) polishing a part of the film by CMP, irradiating the photodiode with light through the film, measuring a current generated in the photodiode, and repeating the polishing and the measurement;
A step (c) of deciding when to finish the polishing based on the result of the measurement;
And (d) ending the polishing at a time determined in the step (c). In claim 1 or 2,
The step (b) includes a step of calculating the light transmittance of the film from a current value obtained by measuring a current generated in the photodiode. In any one of Claims 1 thru | or 3,
The method of manufacturing a semiconductor device, wherein the time of the step (c) is when the result of the measurement falls within a desired current value range. In any one of Claims 1 thru | or 4,
Measuring the current generated in the photodiode in the step (b) is performed by bringing a prober of a measuring instrument into contact with an electrode pad electrically connected to the photodiode and formed on the semiconductor wafer. A method of manufacturing a semiconductor device, comprising: measuring a current generated by light received by the photodiode by a detector. In claim 1,
Measuring the current generated in the photodiode in the step (b) is performed by bringing a prober of a measuring instrument into contact with an electrode pad electrically connected to the photodiode and formed on the semiconductor wafer. Measuring the current generated by the light received by the photodiode by means of a detector,
The method of manufacturing a semiconductor device, wherein the film formation in the step (b) is to form the film while covering the electrode pad with a cover. In any one of Claims 1 thru | or 6,
The method of manufacturing a semiconductor device, wherein the light applied to the photodiode in the step (b) is light having a plurality of wavelengths. A film forming mechanism for forming a film;
A light source;
A measuring instrument with a prober;
A control unit,
The said control part forms into a film with the said film-forming mechanism, measures an optical characteristic with the said light source and the said measuring device, and controls the said film-forming mechanism based on the measurement result. In claim 8,
The control unit forms a film on the photodiode of the semiconductor wafer by the film formation mechanism, irradiates the photodiode with light through the film by the light source, and generates a current generated in the photodiode by the measuring instrument. Measure, control to repeat the film formation and the measurement, determine the time to end the film formation based on the measurement result, and control the film formation mechanism to end the film formation at that time A film forming apparatus. In claim 9,
Measuring the current generated in the photodiode is electrically connected to the photodiode, the prober is brought into contact with an electrode pad formed on the semiconductor wafer, and received by the photodiode by the measuring instrument. Measuring the current generated by light,
A film forming apparatus comprising a cover that covers the electrode pad when the film is formed by the film forming mechanism. In claim 9 or 10,
The film forming mechanism includes a film forming source having a shower head having a smaller diameter than the semiconductor wafer, and a rotating mechanism for rotating the shower head. A polishing mechanism for polishing the film by CMP;
A light source;
A measuring instrument with a prober;
A control unit,
The CMP apparatus characterized in that the control unit polishes the film with the polishing mechanism, measures optical characteristics with the light source and the measuring instrument, and controls the polishing mechanism based on the measurement result. In claim 12,
The control unit polishes a film formed on the photodiode of the semiconductor wafer by the polishing mechanism, irradiates the photodiode with light through the light source by the light source, and generates at the photodiode by the measuring instrument. Measuring the current, controlling to repeat the polishing and the measurement, determining a time to end the polishing based on the measurement result, and controlling the polishing mechanism to end the polishing at that time A CMP apparatus. In claim 13,
Measuring the current generated in the photodiode is electrically connected to the photodiode, the prober is brought into contact with an electrode pad formed on the semiconductor wafer, and received by the photodiode by the measuring instrument. A CMP apparatus characterized by measuring a current generated by light.

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