JP5465828B2 - Substrate processing apparatus and semiconductor device manufacturing method - Google Patents

Description

  The present invention relates to a semiconductor manufacturing apparatus for manufacturing a semiconductor device by generating plasma and subjecting the surface of a substrate such as a silicon wafer to plasma processing such as oxidation, impurity diffusion, thin film generation, and etching. .

  As a semiconductor manufacturing apparatus that performs plasma processing on a substrate, there is a modified magnetron type plasma processing apparatus (hereinafter referred to as MMT apparatus) that can generate high-density plasma by an electric field and a magnetic field (see, for example, Patent Document 1).

  The MMT apparatus has a reaction chamber in which airtightness is ensured, the substrate is accommodated in the reaction chamber, the substrate is heated by a required heating means, and a processing gas is supplied in a shower form from the upper part of the reaction chamber. Is maintained at a predetermined processing pressure.

  A high frequency power is supplied to a ring electrode provided on the outer periphery of the reaction chamber to form an electric field, and a magnetron discharge is generated by applying a magnetic field by a magnet provided around the ring electrode. The electrons emitted from the ring-shaped electrode continue to circulate in a cycloidal motion while drifting, so that the lifetime is increased and the ionization generation rate is increased, so that high-density plasma can be generated. Substrate processing such as forming a thin film on the surface of the substrate by performing chemical reaction by exciting and decomposing the deposition gas with this plasma is performed.

  In the course of substrate processing, the substrate is heated to 150 ° C. to 850 ° C. A halogen lamp that emits infrared light is used as one of the heating means.

  A plurality of halogen lamps are arranged in a plane so as to face the substrate, and the substrate is heated by radiant heating by infrared light emitted from the halogen lamp. In order to efficiently perform radiant heating, a reflection plate or reflection surface is formed on the opposite side of the halogen lamp so that infrared light emitted from the halogen lamp to the opposite side of the substrate is directed to the substrate. It has become.

  FIG. 4 shows an example of a halogen lamp, and the halogen lamp 1 shown in FIG. 4 has a heating portion 2 facing the substrate in a ring shape.

  The halogen lamp 1 has a structure in which a heating wire 4 is housed in a quartz tube 3, and the quartz tube 3 is continuous with the ring-shaped portion 5 and the ring-shaped portion 5, and is perpendicular to the ring-shaped portion 5. The vertical end 6 is bent, and the vertical end 6 airtightly penetrates the reflector or the ceiling of the reaction chamber to expose the upper end. The vertical end 6 supports the halogen lamp 1. It is like.

  The heating portion 4 is accommodated in the ring-shaped portion 5 to constitute the heating portion 2, and the lead wire 8 that is a non-heating element is accommodated in the vertical end portion 6. An insulating terminal portion 7 is provided at the upper end of the vertical end portion 6 to support the lead wire 8, and the lead wire 8 is welded to the heating wire 4 through a metal foil 9. Further, electric power is supplied to the heating wire 4.

  In the heating means using the halogen lamp 1 as a heating element, the lead wire 8 which is a non-heating element is accommodated in the vertical end 6 so as not to generate heat from the vertical end 6. It is considered that the structural parts such as the reflector, the ceiling part, and the lamp fixing part are not heated by the heat from 6.

  However, a reflector is provided for the ring-shaped portion 5, but a reflector or the like is not particularly provided for the vertical end portion 6, so that radiant heat from the heating unit 2 is applied to the vertical portion 6. There has been a phenomenon in which structural parts such as a ceiling part and a lamp fixing part are heated through the end part 6.

  For this reason, a heat-resistant measure and a heat-resistant structure are required, such as using a heat-resistant material for the support portion of the vertical end portion 6 or the penetration portion.

  Even when the halogen lamp 1 has a rod shape, vertical ends 6, that is, fixed portions are formed at both ends, which has a similar problem.

JP 2005-276998 A

  In view of such a situation, the present invention is configured such that both ends of the halogen lamp, the fixed portions of the both ends, and the adjacent structure are not heated by heat radiation from the heating section.

  The present invention provides a semiconductor manufacturing apparatus including a lamp heating unit as a substrate heating means, wherein the lamp of the lamp heating unit includes a heating portion facing the substrate and an end continuous to the heating portion. Is related to a semiconductor manufacturing apparatus covered with an end cover that reflects radiant heat from the end.

  According to the present invention, in a semiconductor manufacturing apparatus comprising a lamp heating unit as a substrate heating means, the lamp of the lamp heating unit comprises a heating part facing the substrate and an end continuous to the heating part, Since the end portion is covered with an end cover that reflects the radiant heat from the end portion, both end portions of the lamp, the fixed portions at both end portions, and the adjacent structure portion are heated by heat radiation from the heating portion. Demonstrate the excellent effect of preventing.

  The best mode for carrying out the present invention will be described below with reference to the drawings. 1 to 3 that are the same as those in FIG.

  First, FIG. 1 shows an example of a semiconductor manufacturing apparatus using plasma in which the present invention is implemented, and an MMT apparatus 11 that performs plasma processing on a substrate such as a wafer using a modified magnetron type plasma source (Modified Magnetron Type Plasma Source). Will be described.

  The MMT apparatus 11 includes a processing container 12, which is formed by a dome-shaped upper container 13 as a first container and a bowl-shaped lower container 14 as a second container, The upper container 13 is placed on the lower container 14, and an airtight processing chamber 15 is defined by the lower container 14 and the upper container 13.

  The upper container 13 is made of a non-metallic material such as aluminum oxide or quartz, and the lower container 14 is made of a metal material such as aluminum. Further, a light transmissive window portion 16 is disposed on the ceiling surface of the processing container 12, and a lamp heating unit 17 as a second heating unit is provided outside the processing container 12 with respect to the light transmissive window portion 16. ing.

  Further, a susceptor 18 which is a heater-integrated substrate holder (substrate holding means) on which the first heating unit is mounted facing the lamp heating unit 17 is provided. The susceptor 18 is made of aluminum nitride, ceramics, quartz, or the like. By using this non-metallic material, metal contamination taken into the film during substrate processing is reduced.

  The shower head 19 is provided in the upper part of the processing container 12, and has a ring-shaped frame 21, the light transmissive window portion 16, a gas introduction port 22, a buffer chamber 23, an opening 24, and a shielding plate 25. And a gas outlet 26. The buffer chamber 23 functions as a dispersion space for dispersing the gas introduced from the gas introduction port 22.

  A gas supply pipe 27 for supplying gas is connected to the gas introduction port 22. The gas supply pipe 27 includes a valve 28 that is an on-off valve and a mass flow controller 29 that is a flow rate controller (flow rate control means). The reaction gas 31 is connected to a gas cylinder (not shown).

  The reaction gas 31 is supplied from the shower head 19 to the processing chamber 15, and the gas after the substrate processing flows from the periphery of the susceptor 18 toward the bottom of the processing chamber 15 to the side wall of the lower container 14. A gas exhaust port 32 for exhausting gas is provided. A gas exhaust pipe 33 is connected to the gas exhaust port 32. The gas exhaust pipe 33 is connected to a vacuum pump 36, which is an exhaust device, via an APC 34, which is a pressure regulator, and a valve 35, which is an on-off valve. ing.

  As a discharge mechanism (discharge electrode) that excites the supplied reaction gas 31, a cylindrical electrode 37 that is a first electrode formed in a cylindrical shape, for example, a cylindrical shape, is provided. The cylindrical electrode 37 is installed on the outer periphery of the processing vessel 12 (upper vessel 13) and surrounds the plasma generation region 38 of the processing chamber 15. A high frequency power supply 41 for applying high frequency power is connected to the cylindrical electrode 37 via a matching unit 39 that performs impedance matching.

  The cylindrical electrode 37, the matching unit 39, the high-frequency power source 41, etc. constitute a plasma generation unit.

  Further, the cylindrical magnet 43 which is a cylindrical magnetic field forming mechanism (magnetic field forming means) formed in a cylindrical shape, for example, is a cylindrical permanent magnet. The cylindrical magnet 43 is disposed near the upper and lower ends of the outer surface of the cylindrical electrode 37. The upper and lower cylindrical magnets 43, 43 have magnetic poles at both ends (inner peripheral end and outer peripheral end) along the radial direction of the processing chamber 15, and the magnetic poles of the upper and lower cylindrical magnets 43, 43 are reversed. It is set to be. Therefore, the magnetic poles in the inner peripheral portion are different from each other, and thereby magnetic lines of force are formed in the cylindrical axial direction along the inner peripheral surface of the cylindrical electrode 37.

  In the center of the bottom side of the processing chamber 15, the susceptor 18 is arranged as a substrate holder (substrate holding means) for holding a wafer 44 as a substrate. The susceptor 18 is formed of, for example, a non-metallic material such as aluminum nitride, ceramics, or quartz, and a heater (not shown) as a heating mechanism (heating means) is integrally embedded in the wafer 44. Can be heated. The heater is adapted to heat the wafer 44 to about 700 ° C. by applying electric power.

  The susceptor 18 is also equipped with a second electrode (not shown) that is an electrode for changing impedance, and the second electrode is grounded via an impedance variable mechanism 45. ing. The variable impedance mechanism 45 is composed of a coil and a variable capacitor, and the potential of the wafer 44 can be controlled via the electrode and the susceptor 18 by controlling the number of coil patterns and the capacitance value of the variable capacitor. ing.

  The processing furnace 46 for processing the wafer 44 by magnetron discharge with a magnetron type plasma source includes at least the processing chamber 15, the processing container 12, the susceptor 18, the cylindrical electrode 37, the cylindrical magnet 43, and the shower. The head 19 and the gas exhaust port 32 are configured, and the wafer 44 can be subjected to plasma processing in the processing chamber 15.

  Around the cylindrical electrode 37 and the cylindrical magnet 43, the electric field and magnetic field formed by the cylindrical electrode 37 and the cylindrical magnet 43 do not adversely affect the external environment and other processing furnaces. Further, a shielding case 47 that effectively shields an electric field and a magnetic field is provided.

  The susceptor 18 is insulated from the lower container 14 and is provided with a susceptor elevating mechanism (elevating means) 48 for elevating the susceptor 18. The susceptor 18 is provided with through holes 49, and on the bottom surface of the lower container 14, wafer push-up pins 51 for pushing up the wafer 44 are provided in at least three places. When the susceptor 18 is lowered by the susceptor elevating mechanism 48, the through hole 49 has a positional relationship such that the wafer push-up pin 51 protrudes through the through hole 49 without being in contact with the susceptor 18. The wafer push-up pins 51 are disposed.

  A gate valve 52 serving as a gate valve is provided on the side wall of the lower container 14. When the gate valve 52 is open, a wafer 44 is carried into or out of the processing chamber 15 by a transfer mechanism (transfer means) (not shown). The process chamber 15 can be hermetically closed when closed.

  The controller 53 as a control unit (control means) includes the APC 34, the valve 35, and the vacuum pump 36 through the signal line A, the susceptor lifting mechanism 48 through the signal line B, and the gate valve 52 through the signal line C. The matching unit 39 and the high frequency power source 41 through the signal line D, the mass flow controller 29 and the valve 28 through the signal line E, and the heater and the impedance variable mechanism embedded in the susceptor 18 through the signal line (not shown). 45 is configured to control the lamp heating unit 17 through the signal line F, respectively.

  Next, using the processing furnace having the above-described configuration, a predetermined plasma process is performed on the surface of the wafer 44 or the surface of the base film formed on the wafer 44 as one step of the semiconductor device manufacturing process. A method will be described. In the following description, the operation of each part constituting the MMT apparatus 11 is controlled by the controller 53.

  The wafer 44 is transferred from the outside of the processing chamber 15 into the processing chamber 15 by a transfer mechanism (not shown) and transferred onto the susceptor 18. The details of this transport operation are as follows.

  The susceptor 18 is lowered to the substrate transfer position, and the tip of the wafer push-up pin 51 passes through the through hole 49. At this time, the push-up pin 51 is projected by a predetermined height from the surface of the susceptor 18. Next, the gate valve 52 is opened, and the wafer 44 is placed on the tip of the wafer push-up pin 51 by a transfer mechanism (not shown).

  When the transfer mechanism is retracted out of the processing chamber 15, the gate valve 52 is closed. When the susceptor 18 is raised by the susceptor elevating mechanism 48, the wafer 44 can be placed on the upper surface of the susceptor 18, and the wafer 44 is further raised to a processing position.

  The heater embedded in the susceptor 18 is preheated, and heats the loaded wafer 44 to a predetermined wafer processing temperature within a range of 150 ° C to 700 ° C.

  Using the vacuum pump 36 and the APC 34, the pressure of the processing chamber 15 is maintained at a predetermined pressure within a range of 1 Pa to 200 Pa.

  When the temperature of the wafer 44 reaches the processing temperature and stabilizes, a nitrogen-containing gas is introduced from the gas inlet 22 toward the upper surface (processing surface) of the wafer 44 through the gas outlet 26 of the shielding plate 25. To do. The gas flow rate at this time is a predetermined flow rate (for example, 100 sccm to 500 sccm).

  At the same time, high frequency power is applied to the cylindrical electrode 37 from the high frequency power supply 41 via the matching unit 39. The power to be applied is a predetermined output value within the range of 100W to 1000W. At this time, the impedance variable mechanism 45 is controlled in advance so as to have a desired impedance value.

  A magnetron discharge is generated under the influence of the magnetic field of the cylindrical magnets 43, 43, and charges are trapped in the upper space of the wafer 44 to generate high-density plasma in the plasma generation region 38. Then, the surface of the wafer 44 on the susceptor 18 is subjected to plasma processing by the generated high density plasma.

  When the plasma processing is finished, the power supply to the cylindrical electrode 37 is stopped, and the nitrogen-containing gas is exhausted from the processing chamber 15. After evacuation, the wafer 44 is transferred out of the processing chamber 15 by a transfer mechanism (not shown) in the reverse order of substrate loading.

  Next, the lamp heating unit 17 will be described with reference to FIGS. In FIG. 2, the position and orientation of the support portion of the vertical end portion 6 of the halogen lamp 1 are changed for convenience in order to clarify the support structure.

  A plurality of lamp storage grooves 56 are engraved on the lower surface of the aluminum reflection block 55 on multiple concentric circles, the inner surface of the lamp storage groove 56 is mirror-finished, and the reflection block 55 is a radiant heat reflection plate. . The mirror finish is gold-plated or vapor-deposited.

  Further, an air cooling space 57 is formed at an intermediate portion of the reflection block 55 and above the lamp housing groove 56, and a cooling pipe 58 is buried above the air cooling space 57, and the cooling pipe 58 is formed in the reflection block. A cooling path is formed inside 55.

  The lamp housing groove 56 houses the heating unit 2 of the halogen lamp 1 (see FIG. 4), and the vertical end 6 of the halogen lamp 1 passes through the reflection block 55 and protrudes upward. The vertical end 6 is covered with an end cover 59 having an oval cross section. The end cover 59 is made of metal, for example, aluminum, and at least the inner surface is mirror-finished. As a mirror finishing method, a gold reflective layer is formed in the same manner as the lamp housing groove 56. Alternatively, it may be made of a stainless steel plate and the inner surface may be mirror polished. The gap between the end cover 59 and the vertical end 6, at least the upper end portion of the gap, is sealed with an insulating material 60. By sealing the gap with the insulating material 60, radiation of radiant heat from the gap can be prevented.

  A lamp fixing plate 62 is provided on the upper surface of the reflection block 55 via a spacer 61, and an L-shaped lamp support member 63 is fixed to the lamp fixing plate 62. The vertical end 6 is fixed to the lamp fixing plate 62. A terminal plate (not shown) for supplying electric power to the halogen lamp 1 is attached to the lamp fixing plate 62.

  The air cooling space 57 is provided with a cooling air discharge nozzle 64, and cooling air supplied from a cooling air supply source (not shown) is discharged and flows into the air cooling space 57, whereby the reflection block 55 is air cooled. Further, a coolant such as cooling water flows through the cooling pipe 58, whereby the reflection block 55 is cooled with water (liquid cooling). Therefore, the temperature rise of the reflection block 55 is suppressed by air cooling and water cooling, and particularly the temperature of the lamp fixing plate 62 is lowered, and it is possible to prevent the members such as the terminal plate provided on the lamp fixing plate 62 from being burned out. Is extended.

  In the figure, reference numeral 65 denotes a heating unit cover that covers the entire lamp heating unit 17.

  When electric power is supplied to the halogen lamp 1 through the insulating terminal portion 7 to cause the halogen lamp 1 to generate heat, 2700 K of infrared rays, for example, are radiated from the halogen lamp 1 and the opposing wafer 44 is heated.

  Infrared radiation radiated from the surface of the heating unit 2 facing the wafer 44 directly heats the wafer 44 from the opening of the lamp housing groove 56 and radiates from the remaining surface of the lamp housing groove 56. Is reflected by the reflecting surface and heats the wafer 44.

  A part of the radiation emitted from the heating unit 2 is reflected by the inner surface of the end cover 59 toward the vertical end 6 and is filled between the end cover 59 and the vertical end 6. The insulating material 60 is cut off. Therefore, infrared rays are not radiated to the surroundings through the vertical end 6 and the surroundings of the vertical end 6 are prevented from being heated.

  Therefore, heating of the support portion of the vertical end portion 6 or the through portion is prevented, burnout is prevented, the life is extended, and the heat resistant structure is simplified.

(Appendix)
The present invention includes the following embodiments.

  (Supplementary Note 1) In a semiconductor manufacturing apparatus including a lamp heating unit as a substrate heating means, the lamp of the lamp heating unit includes a heating portion facing the substrate and an end continuous to the heating portion, and the end Is covered with an end cover that reflects radiant heat from the end.

  (Supplementary note 2) The semiconductor manufacturing apparatus according to supplementary note 1, wherein a gap between the end portion and the end portion cover is sealed with an insulating material, and the insulating material blocks heat radiation.

  (Additional remark 3) The said lamp heating unit has a reflecting plate which reflects the radiant heat of a halogen lamp toward a board | substrate, an air cooling space is formed in this reflecting plate, and the said reflecting plate is by the air supplied to the said air cooling space The semiconductor manufacturing apparatus of Supplementary note 1 to be cooled.

  (Additional remark 4) The said lamp heating unit has a reflecting plate which reflects the radiant heat of a halogen lamp toward a board | substrate, a cooling path is formed in this reflecting plate, and a said refrigerant | coolant flows into this cooling path, and the said reflection The semiconductor manufacturing apparatus according to appendix 1, wherein the plate is liquid-cooled.

It is sectional drawing which shows an example of the semiconductor manufacturing apparatus with which this invention is implemented. It is sectional drawing of the lamp heating unit in this semiconductor manufacturing apparatus. It is an AA arrow line view of FIG. It is a perspective view which shows an example of a halogen lamp.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Halogen lamp 2 Heating part 4 Heating wire 6 Vertical end part 7 Insulated terminal part 17 Lamp heating unit 18 Susceptor 37 Cylindrical electrode 38 Plasma generation area 43 Cylindrical magnet 55 Reflection block 56 Lamp storage groove 57 Air cooling space 58 Cooling pipe 59 End Cover 60 Insulating material 64 Cooling air discharge nozzle

Claims (3)

  A processing chamber having a substrate holder; and a lamp heating unit facing the substrate holder and provided through a window disposed on a ceiling surface of the processing chamber, the lamp of the lamp heating unit being attached to the substrate It has an opposite heating part and an end continuous to the heating part, and the end is covered with an end cover that reflects radiant heat from the end, and the gap between the end and the end cover is insulated. A substrate processing apparatus sealed with a material. The lamp heating unit has a reflection block the lamp receiving groove on the processing chamber side is provided, wherein the heating portion is disposed in the lamp housing groove, the said end portion through said reflector block reflecting block The substrate processing apparatus according to claim 1, wherein the substrate processing apparatus projects upward.   A step of transporting a substrate to a processing chamber having a substrate holder; and a lamp heating unit that is provided through a window disposed on a ceiling surface of the processing chamber so as to face the substrate holder. The lamp of the unit includes a heating portion facing the substrate and an end continuous to the heating portion, and the end is covered with an end cover that reflects radiant heat from the end, and the end and the end And a step of heating the substrate by the lamp heating unit in which a gap between the covers is sealed with an insulating material.

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