JP2013219146A - Semiconductor device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device manufacturing method which can reduce processes necessary for formation of a TSV.SOLUTION: A semiconductor device manufacturing method comprises: a ZrBO film formation process of forming a ZrBO film 64 on a surface of an upper side silicon substrate 63 having a through hole H extending in a thickness direction of the upper side silicon substrate 63, and on an inner surface of the through hole H; and an etching process of dry etching the ZrBO film 64 formed on a bottom face of the through hole H. In the ZrBO film formation process, Zr(BH)-containing gas and activated oxygen-containing gas are supplied to the heated upper side silicon substrate 63, the Zr(BH)-containing gas decomposed on the upper side silicon substrate 63 is oxidized by the oxygen-containing gas, and the ZrBO film 64 is formed on the upper side silicon substrate 63. Further, in the etching process, negative bias voltage is applied to the substrate S, and an etchant of the ZrBO film 64 is drawn to the surface of the upper side silicon substrate 63.

Description

The technology of the present disclosure relates to a semiconductor device, and more particularly, to a method of manufacturing a semiconductor device that manufactures a semiconductor device having a ZrBO film as an insulating film formed on a semiconductor substrate. Here, the ZrBO film is a zirconium boride oxide film, and is a film formed by, for example, an oxynitriding reaction of Zr (BH ₄ ) ₄ .

  2. Description of the Related Art Conventionally, many attempts have been made to increase the degree of element integration while reducing the mounting area of an element substrate by three-dimensionally mounting an element substrate, which is a silicon substrate on which elements are formed.

  In such a three-dimensional mounting, as described in Patent Document 1, for example, an electrode that penetrates a silicon substrate (through silicon via (TSV)) is connected between elements formed on different element substrates. Is being used. According to TSV, it is possible to further reduce the mounting area of the element substrate as much as the area for drawing the wire is not required, compared to the connection by wire bonding.

JP 2011-86850 A

By the way, formation of TSV requires at least the following steps. First, a through hole extending in the thickness direction of the silicon substrate is formed by, for example, dry etching using plasma generated from a fluorine-containing gas. Then, an insulating film made of SiO ₂ or the like that insulates the silicon substrate and the TSV embedded in the through hole is formed by, for example, a CVD method. Next, the insulating film formed on the bottom surface of the through hole is etched in order to make the end of the TSV and the connection destination thereof conductive. At this time, for example, dry etching is used as in the case of forming the through hole. Then, after the barrier metal is formed on the inner surface of the through hole by, for example, sputtering, TSV is formed in the through hole by, for example, plating.

  Moreover, at the time of the dry etching described above, a mask pattern is usually formed in a region other than the region to be etched in order to protect the region not to be etched. Therefore, resist application, exposure, and development are further required for each etching step.

  On the other hand, the connection by wire bonding completes the electrical connection of the element substrate by forming electrode pads on each element substrate to be connected and then connecting the electrodes with wires.

  As described above, according to TSV, although it is possible to reduce the mounting area of the element substrates, the number of processes necessary for connecting the element substrates is greatly increased. Since such an increase in the number of processes leads to an increase in time and cost required for mounting one element substrate, it is desired to reduce the processes necessary for forming the TSV.

  The technology of the present disclosure has been made in view of the above circumstances, and an object thereof is to provide a method for manufacturing a semiconductor device that can reduce the steps necessary for forming a TSV.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
One aspect of the present disclosure includes a ZrBO film forming process in which a ZrBO film is formed on a surface of a semiconductor substrate having a recess extending in a thickness direction of the semiconductor substrate, and the ZrBO film formed on the bottom surface of the recess is dry. An etching step for etching, and in the ZrBO film forming step, a Zr (BH ₄ ) ₄ -containing gas and an activated oxygen-containing gas are supplied to the entire surface of the heated semiconductor substrate, and the semiconductor The Zr (BH ₄ ) ₄ -containing gas decomposed on the substrate is oxidized by the oxygen-containing gas, thereby forming a ZrBO film on the semiconductor substrate. In the etching step, the ZrBO film is formed on the semiconductor substrate. A negative bias voltage is applied, and the etchant of the ZrBO film is drawn into the surface of the semiconductor substrate by the bias voltage, rBO film is etched directly.

According to the above-described aspect, in the ZrBO film forming process, the oxygen-containing gas is supplied to the Zr (BH ₄ ) ₄ decomposed by the heat of the semiconductor substrate, whereby the thermally decomposed Zr (BH ₄ ). ₄ and an oxygen-containing gas form a ZrBO film on the surface of the semiconductor substrate.

As described above, the ZrBO film is formed by reacting the decomposition product of the thermal decomposition of Zr (BH ₄ ) ₄ with the oxygen-containing gas. Therefore, a ZrBO film having a shape along the surface of the semiconductor substrate including the inner surface of the recess is formed. That is, the ZrBO film is an insulating film having a high step coverage as compared with an insulating film formed by depositing a film-forming species formed by a reaction in a gas phase on a substrate.

Here, the incidence probability of Zr (BH ₄ ) ₄ is greater on the surface of the semiconductor substrate than on the inner surface of the recess. As a result, Zr (BH ₄ ) ₄ that is thermally decomposed on the surface of the semiconductor substrate is larger than Zr (BH ₄ ) ₄ that is thermally decomposed on the inner surface of the recess. In addition, the incidence probability of the oxygen-containing gas is larger on the surface of the semiconductor substrate than on the inner surface of the recess. Therefore, the reaction between the decomposition product of Zr (BH ₄ ) ₄ and the oxygen-containing gas is relatively easy to proceed on the surface of the semiconductor substrate. Therefore, the ZrBO film is formed in a shape along the surface of the semiconductor substrate and the inner surface of the recess, and the film thickness on the surface of the semiconductor substrate is larger than the film thickness on the inner surface of the recess.

  In addition, when the ZrBO film formed on the bottom surface of the recess is etched, a negative bias voltage is applied to the semiconductor substrate to draw the etchant of the ZrBO film into the surface of the semiconductor substrate. Therefore, the surface of the semiconductor substrate and the ZrBO film formed on the bottom surface of the recess are more easily etched than the ZrBO film formed on the side surface of the recess. Therefore, even if the ZrBO film is directly etched without forming a mask pattern covering the ZrBO film formed on the surface of the semiconductor substrate and the ZrBO film formed on the side surface of the recess, the surface of the semiconductor substrate and the recess On the side surface, the ZrBO film is maintained even after the etching of the ZrBO film formed on the bottom surface.

  As a result, according to the above-described aspect, it is possible to maintain the state where the entire recess is covered with the ZrBO film without using a mask pattern in the etching process, thereby reducing the number of processes necessary for forming the TSV. It becomes possible.

In another aspect of the method for manufacturing a semiconductor device according to the present disclosure, the Zr (BH ₄ ) ₄ -containing gas is supplied from a first supply hole to a film formation chamber in which the ZrBO film is formed on the semiconductor substrate. The oxidation-containing gas is supplied to the film forming chamber from a second supply hole that is independent of the first supply hole.

According to the above-described aspect, the Zr (BH ₄ ) ₄ -containing gas and the oxygen-containing gas are supplied from the supply holes independent of each other to the film formation chamber in which the ZrBO film is formed on the semiconductor substrate. . Therefore, by avoiding mixing of the Zr (BH _{4) 4} containing gas and the oxidation gas in the preceding stage of the film forming chamber, and the Zr (BH _{4) 4} containing gas and the oxidizing gas, before reaching the semiconductor substrate The chance of contact can be reduced. As a result, the Zr (BH ₄ ) ₄ -containing gas and the oxidizing gas have a higher probability of reacting on the semiconductor substrate, so that the ZrBO film is easily formed on the entire inner surface of the recess.

In another aspect of the method for manufacturing a semiconductor device according to the present disclosure, the oxygen-containing gas is activated by a plasma source connected to a front stage of the second supply hole.
According to the above-described aspect, the activation of the oxygen-containing gas is performed before the second supply hole. Therefore, it is possible to avoid activation of the Zr (BH ₄ ) ₄ -containing gas when the oxygen-containing gas is activated. Therefore, since the ZrBO film formation reaction is more likely to occur on the surface of the semiconductor substrate, the ZrBO film is formed over the entire inner surface of the recess formed in the semiconductor substrate.

In another aspect of the method for manufacturing a semiconductor device according to the present disclosure, in the ZrBO film forming step, supply of the Zr (BH ₄ ) ₄ -containing gas onto the semiconductor substrate and supply of the oxygen-containing gas are alternately performed. As a result, the ZrBO film is formed on the semiconductor substrate.

According to the embodiments described above, Zr _{(BH 4) 4} and the supply of the gas containing, for performing the supply of oxygen-containing gas are alternately, Zr _{(BH 4) 4} adsorbed on the semiconductor substrate at a delivery process gas Zr ( BH ₄ ) ₄ reacts with the oxygen-containing gas that has reached the semiconductor substrate in the oxygen-containing gas supply step. Therefore, compared with the case where Zr (BH ₄ ) ₄ -containing gas and oxygen-containing gas are continuously supplied, the reaction between Zr (BH ₄ ) ₄ and the oxygen-containing gas is more likely to occur on the surface of the semiconductor substrate. Become. Therefore, the ZrBO film is easily formed on the entire inner surface of the through hole.

It is a block diagram showing a schematic structure of a CVD device used for forming a ZrBO film in one embodiment in a manufacturing method of a semiconductor device of this indication. It is a timing chart which shows the drive aspect of the microwave power supply in a CVD apparatus, an oxygen gas supply part, a nitrogen gas supply part, a carrier gas supply part, and an argon gas supply part. It is a block diagram which shows schematic structure of the plasma etching apparatus used for the etching of a ZrBO film | membrane. It is a timing chart which shows the aspect of a high frequency power supply for antennas in a plasma etching apparatus, a current supply part, a high frequency power supply for bias, a halogen content gas supply part, and an oxygen gas supply part. (A)-(c) It is process drawing which shows the manufacturing method of a semiconductor device in order of a process. (A) (b) It is sectional drawing which shows the cross-sectional structure of the ZrBO film | membrane before and behind the etching in an Example. (A) (b) It is sectional drawing which shows the cross-section of the insulating film before and behind the etching in a comparative example. (A)-(d) It is sectional drawing which shows the cross-section of the semiconductor device in one process in the manufacturing method of the semiconductor device in a modification.

Hereinafter, an embodiment embodying a method for manufacturing a semiconductor device according to the present disclosure will be described with reference to FIGS. First, a structure of a plasma CVD apparatus which is an apparatus for forming a ZrBO film included in a semiconductor device will be described with reference to FIG.
[CVD equipment]
As shown in FIG. 1, the CVD apparatus 10 includes a vacuum chamber 11 having an opening in the upper portion, and a lid 12 that closes the opening by being disposed in the upper portion of the vacuum chamber 11. A stage 13 on which the substrate S is placed is disposed in a film forming chamber 11S that is an internal space formed by the vacuum chamber 11 and the lid 12. A resistance heater 13H that heats the substrate S is mounted in the stage 13. The resistance heater 13H heats the temperature of the substrate S placed on the stage 13 to a predetermined temperature, for example, 100 ° C. to 180 ° C., preferably 120 ° C. to 150 ° C. The temperature of the substrate S is maintained at a predetermined temperature during the film forming process. Below the stage 13 is connected an elevating mechanism 14 that moves the stage 13 up and down in the film forming chamber 11S when the substrate S is carried in and out.

  An exhaust unit 15 for exhausting the inside of the film forming chamber 11S is connected to the side of the vacuum chamber 11 through an exhaust port P1. The exhaust unit 15 includes a vacuum pump such as a turbo molecular pump and a dry pump, a main valve for adjusting the pressure in the film forming chamber 11S, and a pressure adjusting valve. When the film forming process is performed in the CVD apparatus 10, the pressure in the film forming chamber 11S is reduced to a predetermined pressure of, for example, 1 Pa to 1000 Pa by adjusting the opening of the pressure adjusting valve.

A shower plate 16 having a plurality of first supply holes H1 and a plurality of second supply holes H2 independent of the first supply holes H1 is attached to the lid 12 on the vacuum chamber 11 side. A raw material tank TK containing Zr (BH ₄ ) ₄ is connected to the first supply hole H 1 via a gas passage 12 a formed inside the lid 12 and a gas port P 2 penetrating the lid 12. .

A carrier gas supply unit 17 that supplies Ar gas, which is a carrier gas, to the raw material tank TK is connected to the raw material tank TK. The temperature of the raw material tank TK is controlled in the range of −2 ° C. to 10 ° C., preferably 0 ° C. to 5 ° C. The raw material tank TK passes Zr (BH ₄ ) ₄ gas containing the carrier gas and the Zr (BH ₄ ) ₄ sublimation gas pushed out by the carrier gas through the gas port P2 and the first supply hole H1. To supply.

An argon gas supply unit 18 that supplies Ar gas is connected to the Zr (BH ₄ ) ₄ supply pipe that connects the raw material tank TK and the lid 12. When the supply of Zr (BH ₄ ) ₄ and the carrier gas is stopped, the argon gas supply unit 18 generates Ar gas having a flow rate corresponding to the sum of the flow rates of these Zr (BH ₄ ) ₄ and the carrier gas. Supply to the membrane chamber. Thereby, for example, when Zr (BH ₄ ) ₄ is intermittently supplied to the film forming chamber 11S, the pressure in the film forming chamber 11S is substantially the same regardless of whether or not Zr (BH ₄ ) ₄ is supplied. Maintained.

  On the other hand, in the second supply hole H2, an oxygen gas supply unit 21 and a nitrogen gas supply unit 22 are provided via a gas passage 12b formed inside the lid 12 and a microwave plasma source PL installed on the top of the lid 12. The argon gas supply unit 23 and the nitrous oxide gas supply unit 24 are connected. These gas supply units 21 to 24 supply each gas to the microwave plasma source PL while metering each gas to a predetermined flow rate.

Inside the microwave plasma source PL installed at the upper part of the gas passage 12b, a heat-resistant discharge tube 25 made of quartz or alumina is disposed. The inside of the discharge tube 25 is connected to the film forming chamber 11 </ b> S through a gas passage 12 b formed inside the lid 12. Inside the discharge tube 25, O ₂ gas, N ₂ gas, and Ar gas supplied from the gas supply units 21, 22, and 23 are predetermined by keeping the pressure in the film forming chamber 11S at a predetermined value. It flows at a flow rate of.

  A microwave source 26 driven by a microwave power source FG is mounted outside the microwave plasma source PL. The microwave source 26 is connected to the microwave plasma source PL via a coaxial cable 27 and a connector 28 for guiding the microwave. An antenna 29 that supplies microwaves into the discharge tube 25 is connected to the connector 28.

  The microwave source 26 outputs, for example, a microwave of 2.45 GHz in a predetermined output range, for example, a range of 0.01 kW to 3.0 kW, by driving power from the microwave power source FG. The coaxial cable 27 guides the microwave output from the microwave source 26 to the inside of the microwave plasma source PL by propagating the microwave to the inside thereof.

  The microwave output from the microwave source 26 is guided to the microwave plasma source PL via the coaxial cable 27 and the connector 28, and then supplied to the discharge tube 25 by the antenna 29 connected to the connector 28. When the microwave source 26 outputs a microwave, the microwave propagated by the coaxial cable 27 is irradiated to the discharge tube 25 via the antenna 29 in the microwave plasma source PL, thereby causing the inside of the discharge tube 25 to be irradiated. The passing gas is activated. The CVD apparatus 10 is configured such that radical components generated by the activation of various gases are supplied into the film forming chamber 11S.

  The CVD apparatus 10 is equipped with a control unit 10C that controls driving of the exhaust unit 15, the gas supply units 17, 18, 21 to 24, and the microwave power source FG. The control device 10C generates a drive signal for these units and a drive current based on the drive signal. Then, the control device 10C drives each unit by outputting the generated drive current.

The microwave power source FG, the microwave plasma source PL, the discharge tube 25, the microwave source 26, the coaxial cable 27, the connector 28, and the antenna 29 described above constitute a plasma source.
[Formation of ZrBO film]
Next, the operation of the CVD apparatus when forming the ZrBO film will be described with reference to FIG. FIG. 2 exemplifies driving modes of each part when N ₂ gas is used as the nitrogen-containing gas. As shown in FIG. 2, when the ZrBO film is formed, first, in a state where the substrate S is carried into the vacuum chamber 11 that has been depressurized to a predetermined pressure, the control device 10C performs oxygen oxygen at the start timing Ts. The gas supply unit 21 and the nitrogen gas supply unit 22 are driven. Thereby, the supply of O ₂ gas, N ₂ gas, and carrier gas into the vacuum chamber 11 is started. The supply flow rates of O ₂ gas and N ₂ gas are, for example, 25 sccm and 475 sccm. At the start timing Ts, the control device 10C may drive the argon gas supply unit 23 in addition to the oxygen gas supply unit 21 and the nitrogen gas supply unit 22. Thereby, Ar gas from the argon gas supply unit 23 may be supplied into the vacuum chamber 11.

Then, the control device 10C drives the microwave power source FG at the timing T1 after Tx seconds from the start timing Ts, whereby the microwave is supplied from the microwave source 26 to the discharge tube 25. The amount of power output from the microwave power source FG is, for example, 50 W as an effective value consumed for excitation of each gas. As a result, the O ₂ gas and the N ₂ gas are activated by the microwave, thereby generating active species including oxygen radicals, nitrogen radicals, and the like.

Next, at timing T2 Tx + Ty seconds after the start timing Ts, the control device 10C drives the carrier gas supply unit 17 to start supply of Zr (BH ₄ ) ₄ and carrier gas. The supply flow rate of the carrier gas is, for example, 100 sccm. At the same time, at timing T <b> 2, the control device 10 </ b> C stops driving the argon gas supply unit 18, thereby stopping the supply of argon gas from the argon gas supply unit 18.

Then, at the end timing Te after Tx + Ty + 120 + Tz seconds from the start timing Ts, the control device 10C stops driving the oxygen gas supply unit 21 and the nitrogen gas supply unit 22, whereby the supply of N ₂ gas and O ₂ gas is performed. Stopped. Further, the control device 10C stops driving the microwave power source FG at timing T3 Ty + 120 seconds after the start timing Ts, that is, Tz seconds before the end timing Te, so that the microwaves to the discharge tube 25 are stopped. Supply is stopped. At the same time, at timing T3, the control device 10C stops driving the carrier gas supply unit 17, thereby stopping the supply of Zr (BH ₄ ) ₄ and the carrier gas. The Tx seconds, Ty seconds, and Tz seconds described above are the gas supply pressure in each gas supply unit, the length of the pipe between each gas supply unit and the film formation chamber 11S, and the exhaust speed in the film formation chamber 11S. It is a time that can be changed as appropriate.

Thus, when Zr (BH ₄ ) ₄ and oxygen radicals, which are activated oxygen, are supplied to the surface of the substrate S, Zr (BH ₄ ) ₄ reacts with the oxygen radicals, thereby causing a reaction on the substrate S and the substrate S. A ZrBO film is formed on the inner surface of the through-hole.
[Characteristics of ZrBO film]
Hereinafter, the formation process of the ZrBO film will be described in more detail. When forming the ZrBO film, first, when Zr (BH ₄ ) _{4 as} a raw material is supplied to the surface of the substrate S, Zr (BH ₄ ) ₄ is adsorbed on the surface of the substrate S. Then, by being heated by the heat of the substrate S, Zr _{(BH 4)} 4 is thermally decomposed. Next, oxygen radicals are supplied to the raw material thermally decomposed on the surface of the substrate S, whereby the pyrolyzed raw material and oxygen radicals react to form a ZrBO film on the surface of the substrate S. It is formed.

As described above, the ZrBO film is not formed only by the reaction of Zr (BH ₄ ) ₄ with oxygen radicals in the gas phase, but by the decomposition product of Zr (BH ₄ ) ₄ by thermal decomposition. It is formed by reaction with oxygen radicals. Therefore, the film formation reaction can be controlled by both the supply of oxygen radicals to the surface of the substrate S and the thermal decomposition of Zr (BH ₄ ) _{4 on} the surface of the substrate S.

For these reasons, when a through hole extending in the thickness direction of the substrate S is formed in the substrate S, a ZrBO film having a shape along the inner surface of the through hole is formed. That is, the ZrBO film is an insulating film formed by depositing a film-forming species formed in the gas phase on the substrate S, for example, an SiO ₂ film formed from a TEOS-containing gas and an O ₂ gas. Compared to the above, it is an insulating film having a higher step coverage.

Here, the incidence probability of Zr (BH ₄ ) ₄ is larger on the surface of the substrate S than on the inner surface of the through hole. Thereby, the Zr (BH ₄ ) ₄ that is thermally decomposed on the surface of the substrate S becomes larger than the Zr (BH ₄ ) ₄ that is thermally decomposed on the inner surface of the through hole. In addition, the incidence probability of oxygen radicals is larger on the surface of the substrate S than on the inner surface of the through hole. Therefore, the reaction between the decomposition product of Zr (BH ₄ ) ₄ and oxygen radicals relatively easily proceeds on the surface of the substrate. Therefore, the ZrBO film is formed in a shape along the surface of the substrate S and the inner surface of the through hole, and the film thickness on the surface of the substrate S is larger than the film thickness on the inner surface of the through hole.
[Plasma etching equipment]
Next, the configuration of a plasma etching apparatus used for dry etching of the ZrBO film will be described with reference to FIG. As shown in FIG. 3, the plasma etching apparatus 30 includes a cylindrical vacuum chamber 31 whose upper surface is open, and a dielectric window 32 that seals the opening of the vacuum chamber 31. The dielectric window 32 is a disk-shaped member made of, for example, quartz. A cylindrical stage 33 is installed in the vacuum chamber 31 at a position facing the dielectric window 32. On the stage 33, the substrate S is placed on a placement surface that is a surface facing the dielectric window 32.

  A high frequency power supply 34 for bias that applies a negative bias voltage to the substrate S is connected to the stage 33 via a matching unit 35 including a blocking capacitor. The high frequency power supply 34 for bias supplies high frequency power having a frequency of 13.56 MHz, for example, to the stage 33. The matching unit 35 matches the output impedance of the bias high-frequency power source 34 with the input impedance of the load including plasma formed in the vacuum chamber 31 when high-frequency power is output from the bias high-frequency power source 34.

An exhaust port 41 that penetrates the vacuum chamber 31 is connected to an exhaust unit 41 that exhausts the interior of the vacuum chamber 31 to a predetermined pressure. The exhaust unit 41 includes a vacuum pump such as a dry pump or a turbo molecular pump, and a valve for controlling the exhaust flow rate of the vacuum pump. In addition, a halogen-containing gas supply unit 42 and an oxygen gas supply unit 43 are connected to the gas port P2 formed through the vacuum chamber 31. The halogen-containing gas supply unit 42 supplies, for example, SF ₆ gas into the vacuum chamber 31 at a predetermined flow rate. The oxygen gas supply unit 43 supplies oxygen gas into the vacuum chamber 11 at a predetermined flow rate.

  Above the dielectric window 32, the high frequency antenna 51 is mounted at a position facing the mounting surface of the substrate S on the stage 33 across the dielectric window 32. The high-frequency antenna 51 has, for example, a spiral upper antenna and a lower antenna that are wound twice and a half. In these upper and lower antennas, inner ends and outer ends are connected to each other.

  An antenna high-frequency power source 52 is connected to the input unit 51 a of the high-frequency antenna 51 via a matching unit 53 and an input-side variable capacitor 54. The input part 51a is formed, for example, at the inner end of the upper antenna. The high frequency power supply 52 for antenna outputs high frequency power of 13.56 MHz to the high frequency antenna 51, for example.

  An output side variable capacitor 55 is connected to the output section 51 b of the high frequency antenna 51. The output part 51b is formed, for example, at the outer end of the upper antenna. The output unit 51b is grounded. When high frequency power is supplied from the antenna high frequency power supply 52 to the high frequency antenna 51, plasma is generated from the gas supplied into the vacuum chamber 31.

  The matching unit 53 matches the output impedance of the antenna high-frequency power source 52 with the input impedance of the load including plasma when high-frequency power is output from the antenna high-frequency power source 52. Further, the output side variable capacitor 55 makes the inductive coupling between the plasma generated in the vacuum chamber 31 and the high frequency antenna 51 substantially uniform throughout the high frequency antenna 51. On the other hand, the input-side variable capacitor 54 is set to a predetermined capacitance value so that the response speed of the matching unit 53 is in an optimum range according to the process conditions.

  Around the dielectric window 32, a magnetic field coil 56 composed of three coils of an upper coil, a middle coil, and a lower coil is disposed. A current supply unit 57 is connected to each of the coils constituting the magnetic field coil 56. The current supply unit 57 supplies current in the same direction to the upper and lower coils, and supplies current in the reverse direction to the middle coil. When a current is supplied from the current supply unit 57 to the magnetic field coil 56, an annular zero magnetic field region is formed at a position surrounded by the middle stage coil in the vacuum chamber 31. Thereby, after the electrons in the vacuum chamber 31 are collected in the zero magnetic field region, a discharge is easily maintained by applying a high-frequency electric field to these electrons.

The plasma etching apparatus 30 is equipped with a control device 30 </ b> C that controls driving of the high-frequency power sources 34 and 52, the exhaust unit 41, the gas supply units 42 and 43, and the current supply unit 57. The control device 30C generates a drive signal for these units and a drive current based on the drive signal. The control device 30C drives each unit by outputting the generated drive current.
[Etching of ZrBO film]
Next, the operation of the plasma etching apparatus 30 when performing dry etching of the ZrBO film formed on the substrate S will be described with reference to FIG. When the etching of the ZrBO film is performed, first, the control device 30C drives the halogen-containing gas supply unit 42 at a timing T1 in a state where the substrate S is loaded into the vacuum chamber 31 that has been decompressed to a predetermined pressure. As a result, a halogen-containing gas having a predetermined flow rate is supplied into the vacuum chamber 31. Further, at timing T <b> 1, the control device 30 </ b> C drives the oxygen gas supply unit 43 to supply a predetermined flow rate of oxygen gas from the oxygen gas supply unit 43 into the vacuum chamber 31.

  The control device 30C drives the antenna high-frequency power source 52 at a timing T2 after a predetermined time from the timing T1, whereby predetermined high-frequency power is supplied to the high-frequency antenna 51. Thereby, plasma is generated from the gas in the vacuum chamber 31. Next, at timing T3 after a predetermined time from timing T2, the control device 30C drives the current supply unit 57, whereby a predetermined current is supplied to the magnetic field coil 56. As a result, a zero magnetic field region is formed in the vacuum chamber 31.

  Then, at timing T4 after a predetermined time from timing T3, the control device 30C drives the bias high frequency power supply 34, whereby a negative bias voltage is applied to the substrate S. With such a bias voltage, positive ions constituting an etchant of the ZrBO film contained in the plasma are drawn into the substrate S, so that the ZrBO film formed on the substrate S is etched. The ZrBO film is also etched by radicals that reach the substrate S.

  When a predetermined time elapses after the etching is started at timing T4, the control device 30C stops driving the bias high-frequency power source 34 at timing T5. Then, at timing T6 after a predetermined time from timing T5, control device 30C stops driving current supply unit 57. Thereafter, at timing T7, the control device 30C stops driving the bias high-frequency power source 34. Thereby, the generation of plasma and the drawing of positive ions are stopped, whereby the etching of the ZrBO film is stopped.

Next, at timing T8 after a predetermined time from timing T7, the control device 30C stops driving the halogen-containing gas supply unit 42, whereby supply of the halogen-containing gas into the vacuum chamber 11 is stopped. Similarly, at timing T8, the control device 30C stops driving the oxygen gas supply unit 43, whereby supply of oxygen gas into the vacuum chamber 11 is stopped.
[Method for Manufacturing Semiconductor Device]
Hereinafter, a method for manufacturing a semiconductor device including a ZrBO film forming process and a ZrBO film etching process will be described with reference to FIGS. In this embodiment, a method for manufacturing a semiconductor device using a via after bonding method in which a TSV is formed after two silicon substrates are bonded through an adhesive layer will be described.

  As shown in FIG. 5A, the substrate S is formed by laminating a lower silicon substrate 61, an adhesive layer 62, and an upper silicon substrate 63 as a semiconductor substrate in this order. Among these, a plurality of element regions 61 a are formed on the surface of the lower silicon substrate 61 on the adhesive layer 62 side. The adhesive layer 62 is made of a resin such as benzocyclobutane. The adhesive layer 62 and the upper silicon substrate 63 are formed with a plurality of substantially cylindrical through holes H as recesses extending in the thickness direction of the upper silicon substrate 63 arranged at a predetermined interval. Each of the through holes H is formed from directly above the element region 61a on the surface of the upper silicon substrate 63 to the surface of the element region 61a.

Then, as shown in FIG. 5B, the formation of the ZrBO film on the substrate S is performed using the above-described CVD apparatus 10. Thus, the Zr (BH ₄ ) ₄ and the activated oxygen gas are supplied to the entire surface of the upper silicon substrate 63 that is the surface of the substrate S and the entire inner surface of the through hole H, whereby the ZrBO film 64 is formed. In this ZrBO film forming step, the deposition rate of the ZrBO film is higher on the surface of the substrate S than on the inner surface of the through-hole H. Therefore, the thickness of the ZrBO film 64 formed on the surface of the substrate S is It becomes larger than the thickness of the ZrBO film on the inner surface of H.

  When the ZrBO film 64 is formed, the ZrBO film 64 formed on the bottom surface of the through hole H is etched using the plasma etching apparatus 30 described above. This etching step is performed without forming a mask pattern that prevents etching of the ZrBO film 64 formed on the portion other than the bottom surface of the through hole H. Accordingly, as shown in FIG. 5B, among the ZrBO films 64 formed on the substrate S, at least the ZrBO film 64 formed on the bottom surface of the through hole H, and the ZrBO formed on the surface of the substrate S. The film 64 is etched directly.

As described above, the etching of the ZrBO film 64 is performed by drawing positive ions into the substrate S. Therefore, most of the positive ions that contribute to the etching of the ZrBO film are almost normal to the surface of the substrate S from the substrate. It becomes easy to reach S. Therefore, compared to Zr (BH ₄ ) ₄ supplied to the substrate S when the ZrBO film is formed, the positive ions reach the surface of the substrate S and reach the bottom surface Hb of the through hole H. The difference of becomes smaller. Therefore, the difference in the etching amount of the ZrBO film between the surface of the substrate S and the bottom surface Hb of the through hole H is larger than the difference in thickness of the ZrBO film 64 formed on the surface of the substrate S and the bottom surface Hb of the through hole H. Becomes smaller. Therefore, even if the ZrBO film is etched so that the upper surface of each element region 41a that is the bottom surface Hb of the through hole H is exposed, the surface of the substrate S is kept covered with the ZrBO film. .

  Further, since positive ions reach the substrate S from the normal direction with respect to the surface of the substrate S, the ZrBO film 64 formed on the side surface of the through hole H compared to the ZrBO film 64 formed on the bottom surface Hb of the through hole H. Is difficult to etch. However, since positive ions reach the side surface of the through-hole H, the ZrBO film formed on the side surface is etched to some extent. In particular, in the vicinity of the bottom surface on the side surface of the through-hole H, the ZrBO film 64 is etched by positive ions reaching the bottom surface Hb, so that the ZrBO film 64 is more easily etched than other portions on the side surface. In this respect, since the ZrBO film 64 formed by the above-described CVD method is formed substantially uniformly with respect to the inner surface of the through hole H, the through hole is also formed at the end of etching of the ZrBO film formed on the bottom surface Hb. The entire side surface of H is easily maintained in a state covered with the ZrBO film.

As described above, by using the ZrBO film 64 as the insulating film of the through hole H, even when the ZrBO film 64 is directly etched when the ZrBO film 64 formed on the bottom surface of the through hole H is etched, A state where the surface is covered with the ZrBO film 64 can be maintained. That is, for example, the number of steps necessary for forming the TSV can be reduced as compared with the case where SiO ₂ formed by the CVD method using TEOS is used as the insulating film because the number of steps necessary for forming the mask pattern can be reduced. Can be reduced. Note that the mask pattern forming step includes, for example, steps of resist application, exposure, and development in the case of forming a resist mask.
[Example]
[Formation of ZrBO film]
A plurality of recesses having a diameter of 6 μm and a depth of 45 μm were formed on a silicon substrate having a diameter of 200 mm. And the ZrBO film | membrane was formed on the following conditions with the above-mentioned plasma CVD apparatus with respect to the silicon substrate in which the recessed part was formed. Note that N ₂ O gas was used as the oxygen-containing gas when forming the ZrBO film.

[Conditions for forming ZrBO film]
・ Electric energy of microwave power source Effective value 90W (setting value 150W)
・ Flow rate of carrier gas 100sccm
・ N ₂ gas flow rate 450sccm
・ N ₂ O gas flow rate 50 sccm
・ Pressure in the vacuum chamber 200Pa
・ Distance between substrate and shower plate: 37mm
Under these formation conditions, the temperature of the silicon substrate is 120 ° C. (Example 1), 130 ° C. (Example 2), 140 ° C. (Example 3), 150 ° C. (Example 4), and 170 ° C. (Example). As 5), a ZrBO film was formed. In Examples 1 to 5, the thicknesses of the ZrBO films on the surface of the silicon substrate were 228.2 nm, 232.2 nm, 228.2 nm, 200.4 nm, and 190.5 nm in this order.

  The step coverage in each example is shown in Table 1 below. In each example, the vicinity of the opening (S1) on the inner surface of the recess, the vicinity of the center in the depth direction on the inner surface of the recess (S2), the vicinity of the bottom surface on the inner surface of the recess (S3), and the bottom surface of the recess (B ) To calculate step coverage. Note that the step coverage is the percentage of the film thickness of the ZrBO film in other parts with respect to the film thickness of the ZrBO film formed on the surface of the silicon substrate.

  As shown in Table 1, it was recognized that the thickness of the ZrBO film formed on the bottom surface of the recess was substantially half that of the ZrBO film formed on the surface of the silicon substrate regardless of the temperature of the substrate. Further, it was recognized that the step coverage increased in the order of the vicinity of the center, the vicinity of the opening, and the vicinity of the bottom surface on the side surface of the recess. In addition, even in the vicinity of the opening with the lowest step coverage, the step coverage value is as high as about 40% or more, so that the ZrBO film with high step coverage is a substantially uniform film over the entire inner surface of the recess. It was recognized that it was formed with a thickness. Such a tendency was recognized even when the electric power of the microwave power source, the flow rate of each gas, and the pressure in the vacuum chamber were changed.

Further, a ZrBO film was formed on the silicon substrate on which the above-described recess was formed, using an oxygen-containing gas when forming the ZrBO film as O ₂ gas. At this time, the power amount of the microwave power source, the pressure in the vacuum chamber, and the flow rate of the N ₂ gas were changed from the above formation conditions as follows.

[Conditions for forming ZrBO film]
・ Electric energy of microwave power source Effective value 50W (set value 100W)
・ N ₂ gas flow rate 475sccm
・ O ₂ gas flow rate 25sccm
・ Pressure inside the vacuum chamber 300Pa
Under these formation conditions, the temperature of the silicon substrate was set to 170 ° C. (Example 6) to form a ZrBO film. The thickness of the ZrBO film on the surface of the silicon substrate was 220 nm. The step coverage in Example 6 is shown in Table 2 below.

As shown in Table 2, when O ₂ gas was used as the oxygen-containing gas, the same tendency as when N ₂ O gas was used was observed. Such a tendency was recognized even when the electric power of the microwave power source, the flow rate of each gas, and the pressure in the vacuum chamber were changed.

  FIG. 6 schematically shows the shape of such a ZrBO film. In FIG. 6, a through hole extending in the thickness direction is formed in the upper silicon substrate 72 laminated on the lower silicon substrate 71. A ZrBO film 73 is formed on the surface of the upper silicon substrate 72 and the inner surface of the through hole. As shown in FIG. 6A, a ZrBO film 73 having a relatively large thickness T is formed on the surface of the upper silicon substrate 72 as compared with the inner surface of the through hole. On the other hand, on the inner surface of the through hole, the thickness S1 near the opening on the inner surface of the through hole, the thickness S2 near the center portion on the inner surface, the thickness S3 near the bottom surface on the inner surface, and the thickness on the bottom surface B is substantially the same. Moreover, as described above, the step coverage is a high value of about 40% or more at any part on the inner surface. As described above, in the ZrBO film 73, a depression toward the side surface is hardly formed at the corner portion formed by the bottom surface and the side surface of the through hole.

Therefore, even if the ZrBO film 73 on the bottom surface of the through hole is etched without a mask pattern, the thickness of the ZrBO film 73 on the bottom surface is set on the surface of the upper silicon substrate 72 as shown in FIG. The ZrBO film 73 having the pulled thickness (T-B) is maintained. In addition, the ZrBO film 73 having the same thickness as that before the etching is maintained on the entire inner surface of the through hole.
[Comparative example]
Similar to the above-described embodiment, a plurality of recesses having a diameter of 6 μm and a depth of 45 μm were formed on a silicon substrate having a diameter of 200 mm. Then, the silicon substrate formed of the recess, by a plasma CVD method using TEOS, which is vaporized by the O ₂ gas and the carrier gas, to form a SiO ₂ film (Comparative Example 1). In addition, a SiN film was formed on a similar silicon substrate using SiH ₄ gas and N ₂ gas (Comparative Example 2).

  In Comparative Example 1 and Comparative Example 2, the thickness of the ZrBO film on the surface of the silicon substrate was 422.7 nm and 450.5 nm in this order. Table 3 below shows the step coverage in each comparative example.

  As shown in Table 3, in both Comparative Example 1 and Comparative Example 2, it was recognized that the step coverage on the bottom surface of the recess was 20% or less. Moreover, it was recognized that the step coverage in the vicinity of the opening was highest on the side surface of the recess. In addition, it was recognized that the step coverage in the region other than the vicinity of the opening on the side surface of the concave portion is significantly smaller than the step coverage in the vicinity of the opening. Such a tendency was recognized even when the flow rates of various gases were changed.

  FIG. 7 schematically shows the shape of such an insulating film. In FIG. 7, as in FIG. 6, a through-hole extending in the thickness direction is formed in the upper silicon substrate 82 stacked on the lower silicon substrate 81. An insulating film 83 is formed on the surface of the upper silicon substrate 82 and the inner surface of the through hole.

For example, when the insulating film 83 is a SiO ₂ film formed by plasma generated from TEOS and oxygen, first, a gas containing carrier gas and TEOS and O ₂ gas are supplied into the vacuum chamber. Then, by generating plasma from these gases, TEOS decomposition products and an active oxidation source exist in the vacuum chamber. For this reason,
A decomposition product from TEOS and an oxidation source react with each other in a gas phase, whereby a film-forming species is formed.

Then, since the SiO ₂ film is formed when the film-forming species in the gas phase reaches the upper silicon substrate 82, as shown in FIG. 7A, the upper silicon substrate 82 where the film-forming species easily reach. The SiO ₂ film is formed in order from the surface. Further, since the range of the incident angle of the film formation species is the largest at the opening portion of the through hole, more film formation species reach the opening portion of the through hole than at other portions. Therefore, on the surface of the upper silicon substrate 82, the thickness T of the insulating film 83 increases toward the opening.

In addition, in the opening, the formed SiO ₂ film grows so as to protrude toward the inside of the through hole. Therefore, the incident angle of the film forming species that can reach the inside of the through hole is from the opening. The smaller the distance, the smaller. For these reasons, the thickness of the insulating film 83 formed on the inner surface of the through hole decreases in the order of the thickness S1 near the opening, the thickness S2 near the center, and the thickness S3 near the bottom. In addition, since the incident amount of the film formation species decreases from the center of the bottom surface toward the outer edge at the bottom surface of the through hole, the thickness B of the insulating film 83 formed on the bottom surface extends from the center of the bottom surface toward the outer surface. Become smaller. As a result, in the insulating film 83, depressions toward the side surface are formed at corners formed by the bottom surface and the side surface of the through hole.

Note that even when the insulating film 83 is a SiN film formed by plasma generated from SiH ₄ gas and N ₂ gas, the same phenomenon as in the case where the SiO ₂ film is formed occurs. Therefore, the shape of the SiN film formed on the upper silicon substrate 82 is substantially the same as the shape of the SiO ₂ film.

  As a result, when the bottom surface of the insulating film 83 is etched without a mask pattern, the protruding amount of the insulating film 83 formed on the surface of the upper silicon substrate 82 is reduced as shown in FIG. 7B. Therefore, the insulating film 83 formed on the bottom surface is etched to the vicinity of the outer edge of the bottom surface. In addition, an insulating film 83 having a thickness (T−B) obtained by subtracting the thickness of the insulating film 83 on the bottom surface is maintained on the surface of the upper silicon substrate 82. Here, as described above, in the vicinity of the bottom surface on the inner surface of the through-hole, the thickness of the insulating film 83 is significantly small, and thus the formed insulating film 83 is often etched. In particular, the insulating film formed at the corner portion of the bottom surface and the side surface of the through hole is etched together with the insulating film formed on the bottom surface. Therefore, when etching the insulating film 83 other than the ZrBO film, if etching is performed without a mask pattern, the upper silicon substrate 82 and the TSV formed in the through hole are not insulated.

  Note that the thickness of the insulating film 83 formed on the inner surface of the through hole can be increased by increasing the formation time of the insulating film 83 and increasing the thickness of the entire insulating film 83. . However, at the same time, on the surface of the upper silicon substrate 82, the amount of the insulating film 83 that protrudes to the inside of the opening of the through hole is increased, so that the coverage ratio of the barrier metal and the TSV filling ratio are decreased. .

According to the embodiment described above, the effects listed below can be obtained.
(1) According to the formation process of the ZrBO film 64, the ZrBO film 64 having a thickness on the surface of the substrate S larger than a thickness on the bottom surface of the through hole H is formed. A ZrBO film 64 along the side surface of the through hole H is also formed. Then, when the ZrBO film 64 is etched, a negative bias voltage is applied to the substrate S, whereby the etchant of the ZrBO film 64 is drawn into the surface of the substrate S. Therefore, the ZrBO film 64 formed on the surface of the substrate S and the bottom surface of the through hole H is more easily etched than the ZrBO film 64 formed on the side surface of the through hole H.

  Therefore, even if a mask pattern covering the ZrBO film 64 formed on the surface of the substrate S and the ZrBO film 64 formed on the side surface of the through hole H is not formed, the surface of the substrate S and the side surface of the through hole H are formed. In this case, the ZrBO film 64 is maintained even after the etching of the ZrBO film 64 formed on the bottom surface. As a result, the entire through hole H can be kept covered with the ZrBO film 64 without using a mask pattern in the etching process, so that the number of processes necessary for forming the TSV can be reduced.

(2) The Zr (BH ₄ ) ₄ -containing gas and the oxygen-containing gas are supplied to the film formation chamber 11S from the supply holes H1 and H2 that are independent from each other. Therefore, by avoiding mixing of the Zr (BH ₄ ) ₄ -containing gas and the oxidizing gas in the previous stage of the film forming chamber 11S, before the Zr (BH ₄ ) ₄ -containing gas and the oxidizing gas reach the substrate S Can reduce the chance of contact. As a result, the Zr (BH ₄ ) ₄ -containing gas and the oxidizing gas are more likely to react on the substrate S, so that a ZrBO film is easily formed on the entire inner surface of the through hole H.

(3) The activation of the oxygen-containing gas is performed by the microwave plasma source PL connected to the front stage of the second supply hole H2. Therefore, it is possible to avoid activation of the Zr (BH ₄ ) ₄ -containing gas when the oxygen-containing gas is activated. Therefore, since the formation reaction of the ZrBO film 64 occurs more easily on the surface of the substrate S, the ZrBO film 64 is formed on the entire inner surface of the through hole H formed in the substrate S.

In addition, each said embodiment can be suitably changed and implemented as follows.
The Zr (BH ₄ ) ₄ -containing gas and the oxygen-containing gas may be supplied from the same supply hole to the film forming chamber 11S. Even in such a configuration, the ZrBO film is easily formed on the entire surface of the substrate S and the inner surface of the through hole H as much as the ZrBO film is formed by utilizing the thermal decomposition of Zr (BH ₄ ) _{4 in} the substrate S. It becomes.

The activation of the oxygen-containing gas may be performed after the second supply hole H2. Even in such a configuration, the ZrBO film is easily formed on the entire surface of the substrate S and the inner surface of the through hole H as much as the ZrBO film is formed by utilizing the thermal decomposition of Zr (BH ₄ ) _{4 in} the substrate S. It becomes.

As a means for bringing the gas containing oxygen atoms into an active state, high-frequency excitation with high-frequency power or excitation with a metal catalyst source such as W may be used.
Process conditions such as the substrate temperature, the pressure in the deposition chamber, and the supply flow rates of various gases during the formation of the ZrBO film can be arbitrarily changed within a range in which the ZrBO film can be formed.

The carrier gas for Zr (BH ₄ ) ₄ is not limited to Ar gas, and other inert gas such as He gas may be used.
As the gas containing, oxygen atom is active, and to use a O ₂ gas and N _{2 O} gas. However, the present invention is not limited to this, and as the gas containing oxygen atoms, NO gas, NO ₂ gas, CO gas, CO ₂ gas, or other gas containing O atoms may be used. Further, as the gas containing oxygen atoms, a mixed gas in which a plurality of gases are selected from the gases listed above, such as a mixed gas of O ₂ gas and N ₂ O gas, may be used. By combining these gases, the oxidation reaction with Zr (BH ₄ ) ₄ can be appropriately selected according to the environment in the film forming chamber and the shape of the film forming target.

- the formation of the ZrBO film was set to the addition of _{N 2} gas. This, O ₂ gas, since the only gas containing oxygen atoms such as N 2 _O gas which may lifetime of the excited state is short, the addition of excited easily and relatively long lifetime N ₂ gas excited state This is because the lifetime of the excited state of the gas containing oxygen atoms can be extended. Note that the ZrBO film may be formed using Ar gas and Ne gas instead of N ₂ gas.

The activated oxygen-containing gas that oxidizes Zr (BH ₄ ) ₄ is not limited to a gas containing oxygen radicals, and the impact of ions in the oxidation process affects the electrical characteristics and shape of the device and the ZrBO film. Otherwise, a gas containing oxygen ions may be used. If Zr (BH ₄ ) ₄ is oxidized by a gas containing oxygen ions, the ZrBO film is formed in such a manner that the substrate S is exposed to high-frequency power or microwave high-frequency plasma in the vacuum chamber 11. May be.

In the ZrBO film forming process, the supply of the Zr (BH ₄ ) ₄ -containing gas and the supply of the activated O ₂ gas may be performed alternately. According to such a configuration, the following effects can be obtained.

_{(4) Zr (BH 4)} 4 and the supply of the gas containing, for performing the supply of oxygen-containing gas are _{alternately, Zr (BH 4) 4 Zr} (BH 4) adsorbed on the substrate S at a delivery process of the gas ₄ Then, the oxygen-containing gas that has reached the substrate S in the oxygen-containing gas supply step reacts. Therefore, the reaction between Zr (BH ₄ ) ₄ and the oxygen-containing gas is more likely to occur on the surface of the substrate S than when the Zr (BH ₄ ) ₄ -containing gas and the oxygen-containing gas are continuously supplied. Become. Therefore, the ZrBO film is easily formed on the entire inner surface of the through hole.

-While oxygen radicals are continuously supplied, Zr (BH ₄ ) ₄ may be supplied intermittently a plurality of times. Accordingly, the supply period of the Zr _{(BH 4)} 4, by Zr _{(BH 4)} 4 reacts with oxygen radicals, ZrBO film is formed on the surface of the substrate S. In the period in which Zr (BH ₄ ) ₄ is not supplied and oxygen radicals are supplied, the ZrBO film is further oxidized by oxygen radicals.

Each of the period for supplying the gas containing oxygen radicals and Zr (BH ₄ ) ₄ at the same time and the period for supplying the gas containing oxygen radicals may be provided once.
・ Tx seconds after starting the supply of O ₂ gas, N ₂ gas, and Ar gas at the start timing Ts, the microwave power source FG is driven to stabilize the pressure in the vacuum chamber 11 after starting the supply of various gases. The O ₂ gas and N ₂ gas were excited stably. That is, the predetermined period Tx from when the supply of various gases is started until the microwave power source is driven can be arbitrarily set as the time until the pressure in the vacuum chamber 11 is stabilized.

The halogen-containing gas is not limited to SF ₆ gas, but includes NF ₃ gas, ClF ₃ gas, F ₂ gas, XeF ₂ gas, HBr gas, Cl ₂ gas, BCl ₃ gas, HCl gas, SiF ₄ gas, CF ₄ Gas, CHF ₃ gas, CCl ₄ gas, CBr ₄ gas, or the like may be used. Further, the ZrBO film may be etched by a mixed gas obtained by mixing a plurality of these gases.

  In the etching process, the gas for etching the ZrBO film may be switched. For example, the halogen-containing gas may be switched to a non-fluorine-containing gas containing a halogen other than the halogen gas.

· O ₂ gas may not be supplied. In this case, the oxygen gas supply unit 43 may be omitted from the plasma etching apparatus 30.
In the etching process, the current supply unit 57 and the power supplies 34 and 52 may be driven simultaneously. Further, the gas supply units 42 and 43, the current supply unit 57, and the power supplies 34 and 52 may be driven simultaneously.

  In the etching step, the driving of the gas supply units 42 and 43 may be stopped after the driving of the current supply unit 57 and the power sources 34 and 52 are stopped simultaneously. The gas supply units 42 and 43, the current supply unit 57, and the power sources 34 and 52 may be stopped simultaneously.

  The plasma etching apparatus 30 may have a configuration in which the magnetic field coil 56 and the current supply unit 57 are omitted, or may have a configuration in which a high-frequency antenna is wound around the side surface of the cylindrical vacuum chamber 11. .

The plasma etching apparatus may be any apparatus capable of generating plasma, such as a capacitively coupled apparatus that has two electrodes facing each other in a vacuum chamber and discharges between them.
-The manufacturing method of the semiconductor device of this indication may be applied to Via first method. In this case, the substrate S has a silicon substrate 91 and a TSV trench Tr formed in the thickness direction of the silicon substrate 91, as shown in FIG. A ZrBO film 92 is formed on the inner wall surface of the trench Tr.

  -The manufacturing method of the semiconductor device of this indication may be applied to the Via middle method. In this case, as shown in FIG. 8B, the substrate S is the same as the substrate S when the TSV is formed by the Via after bonding method except that the element region 91a is formed on the upper surface of the silicon substrate 91. It is the same composition.

  The semiconductor device manufacturing method of the present disclosure may be applied to the Via last method. In the Via last method, in the method in which the TSV is formed from the surface of the silicon substrate 91, the substrate S includes a silicon substrate 91 having an element region 91a on the upper surface, as shown in FIG. The wiring layer 93 stacked on the silicon substrate 91 and the trench Tr penetrating the wiring layer 93 and formed partway in the thickness direction of the silicon substrate 91 are included. A ZrBO film 92 is formed on the upper surface of the wiring layer 93 and the inner wall surface of the trench Tr.

  On the other hand, in the Via last method, in which the TSV is formed from the back surface of the silicon substrate 91, the substrate S has a silicon substrate 91 with an element region 91a formed on the upper surface as shown in FIG. And a wiring layer 93 having a wiring 93 a connected to the element region 91 a and a through hole H penetrating the silicon substrate 91. Further, the substrate S has a supporting glass substrate G bonded to the upper surface of the wiring layer 93 via an adhesive layer (not shown). A ZrBO film 92 is formed on the back surface of the substrate S and the inner wall surface of the through hole H.

  DESCRIPTION OF SYMBOLS 10 ... CVD apparatus, 11, 31 ... Vacuum chamber, 11S ... Film-forming chamber, 12 ... Lid, 12a, 12b ... Gas passage, 13, 33 ... Stage, 13H ... Resistance heater, 14 ... Lifting mechanism, 15 ... Exhaust pump , 16 ... shower plate, 17 ... carrier gas supply unit, 18 ... argon gas supply unit, 21 ... oxygen gas supply unit, 22 ... nitrogen gas supply unit, 23 ... argon gas supply unit, 24 ... nitrous oxide gas supply unit, DESCRIPTION OF SYMBOLS 25 ... Discharge tube, 26 ... Microwave source, 27 ... Coaxial cable, 28 ... Connector, 29 ... Antenna, 30 ... Plasma etching apparatus, 32 ... Dielectric window, 34 ... High frequency power supply for bias, 35, 53 ... Matching device, 41 ... Exhaust section, 42 ... halogen-containing gas supply section, 43 ... oxygen gas supply section, 51 ... high frequency antenna, 52 ... high frequency power supply for antenna, 54 ... input side variable condenser 55 ... Output-side variable capacitor, 56 ... Magnetic coil, 57 ... Current supply unit, 61, 71, 81 ... Lower silicon substrate, 61a, 91a ... Element region, 62 ... Adhesive layer, 63, 72, 82 ... Upper silicon Substrate, 63s ... upper surface, 64, 73, 92 ... ZrBO film, 65 ... photoresist, 83 ... insulating film, 91 ... silicon substrate, 93 ... wiring layer, 93a ... wiring, FG ... microwave power source, G ... supporting glass substrate , H ... through hole, Hb ... bottom surface, H1 ... first supply hole, H2 ... second supply hole, P1 ... exhaust port, P2 ... gas port, PL ... microwave plasma source, S ... substrate, Tr ... trench, TK ... raw material tank.

Claims (4)

A ZrBO film forming step in which a ZrBO film is formed on the surface of the semiconductor substrate having a recess extending in the thickness direction of the semiconductor substrate;
An etching process in which the ZrBO film formed on the bottom surface of the recess is dry-etched,
In the ZrBO film forming step,
Zr (BH ₄ ) ₄ -containing gas and activated oxygen-containing gas are supplied to the entire surface of the heated semiconductor substrate,
The Zr (BH ₄ ) ₄ -containing gas decomposed on the semiconductor substrate is oxidized by the oxygen-containing gas to form a ZrBO film on the semiconductor substrate,
In the etching step,
A negative bias voltage is applied to the semiconductor substrate;
A method of manufacturing a semiconductor device, wherein the ZrBO film is directly etched by drawing the etchant of the ZrBO film to the surface of the semiconductor substrate by the bias voltage. The Zr (BH ₄ ) ₄ -containing gas is
Supplied from the first supply hole to the film formation chamber in which the ZrBO film is formed on the semiconductor substrate;
The oxygen-containing gas is
The method for manufacturing a semiconductor device according to claim 1, wherein the film forming chamber is supplied from a second supply hole independent of the first supply hole. The oxygen-containing gas is
The method of manufacturing a semiconductor device according to claim 2, wherein the semiconductor device is activated by a plasma source connected to a front stage of the second supply hole. In the ZrBO film forming step,
The ZrBO film is formed on the semiconductor substrate by alternately supplying the Zr (BH ₄ ) ₄ -containing gas onto the semiconductor substrate and the oxygen-containing gas. The manufacturing method of the semiconductor device as described in any one of these.

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