KR20100057585A - Manufacturing method of semiconductor apparatus, film forming method and substrate processing apparatus - Google Patents

Abstract

PURPOSE: A manufacturing method of the semiconductor device, and the film forming method and substrate processing apparatus omit the gas purge process by the inactive gas. The throughput is improved. CONSTITUTION: The substrate(3) is accepted to the process chamber(17). It is heated by the temperature which the mood within the process chamber and substrate is preset. The gas which it is preset becomes in the process chamber with the class times. The epitaxial film is selectively formed in the silicon surface of substrate. The gas class times process comprises the first supply process, the first removal process, and the second supply process and the second removal process. The first supply process supplies the silicon contained gas and hydrogen gas towards the central part of substrate. The first removal process eliminates the silicon contained gas from the process chamber. The second supply process supplies the hydrochloric acid gas and hydrogen gas towards the central part of substrate. The second removal process eliminates the hydrochloric acid gas from the process chamber.

Description

TECHNICAL MANUFACTURING METHOD, MANUFACTURING METHOD AND SUBSTRATE PROCESSING METHOD OF SEMICONDUCTOR DEVICE

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing a semiconductor device in which a semiconductor device is manufactured by performing a process such as thin film formation, diffusion of impurities, annealing, etching, or the like on a substrate such as a silicon wafer or a glass substrate.

One of the semiconductor devices is a MOSFET (Metal Oxide Semiconduotor Field Effect Transistor), which is a polymerized structure of a metal, an oxide film, and a semiconductor.

As a problem in miniaturization of MOSFETs and high performance, there is a reduction in contact resistance and the like, and one method of solving this problem is a method of selectively growing a silicon epitaxial film on a source / drain.

Conventionally, the growth of a silicon epitaxial film is carried out by using SiH ₂ Cl ₂ , HCl and H ₂ as processing gases, and supplying these processing gases continuously to the processing chamber at processing temperatures of 750 ° C. to 850 ° C.

The treatment temperature of 750 ℃ to 850 ℃ is a high temperature, and due to the miniaturization and high performance, the effect of thermal damage on the substrate element, thermal budget (thermal budget) increases, which is the cause of the high performance of the device, or the cause of the yield decrease It is.

As a prior art, Japanese Unexamined-Japanese-Patent No. 2003-86511 and Unexamined-Japanese-Patent No. 5-21357 are mentioned.

SUMMARY OF THE INVENTION In view of such circumstances, the present invention provides a method of manufacturing a semiconductor device that enables the production of a high quality production film at low temperature, improves the performance of the device, and improves the yield.

According to the present invention, a substrate having at least a silicon surface and an insulating surface on a surface thereof is housed in a processing chamber, and is selectively epitaxially formed on the silicon surface using a substrate processing apparatus that heats the processing chamber and the substrate to a predetermined temperature by heating means. A method of manufacturing a semiconductor device for growing a film, comprising the steps of loading a substrate into the processing chamber, heating the processing chamber and the substrate to a predetermined temperature, and supplying and supplying a predetermined gas to the processing chamber. The gas supply and drainage process includes a first supply step of supplying silane-based gas and hydrogen gas to the processing chamber, a first removal step of removing at least the silane-based gas from the processing chamber, and chlorine gas. And a second supply step of supplying hydrogen gas to the processing chamber and a second removal step of removing at least the chlorine gas from the processing chamber. Be a method of manufacturing a semiconductor device, which repeatedly executed.

According to the present invention, a substrate having at least a silicon surface and an insulating surface on a surface thereof is housed in a processing chamber, and selectively epitaxially formed on the silicon surface using a substrate processing apparatus for heating the processing chamber and the substrate to a predetermined temperature by heating means. A method of manufacturing a semiconductor device for growing a tactile film, the method comprising: loading a substrate into the processing chamber, heating the processing chamber and the substrate to a predetermined temperature, and supplying and supplying a predetermined gas to the processing chamber; The gas discharging step includes a first supply step of supplying silane-based gas and hydrogen gas to the processing chamber, a first removal step of removing at least the silane-based gas from the processing chamber, and a chlorine gas and hydrogen gas. The second supply step of supplying the processing chamber and the second removal step of removing at least the chlorine gas from the processing chamber are predetermined times. Since it is repeatedly executed, the gas purge step using an inert gas can be omitted in the steps before and after the second supply step, thereby improving throughput, and performing chlorine gas by supplying hydrogen gas together with chlorine gas. Therefore, it exhibits the outstanding effect that the uniformity of a process improves.

Other objects, features and advantages of the present invention will become more apparent from the following detailed description of the embodiments and the accompanying drawings.

1 is a perspective view showing an example of a substrate processing apparatus according to an embodiment of the present invention;
2 is a schematic cross-sectional view of a processing furnace used in the substrate processing apparatus;
3 is a flowchart of a processing step according to the present invention;
4A is a flowchart showing a first film forming step example of the present invention;
4B is a flowchart showing a second film forming step example of the present invention;
5 is an explanatory diagram showing a film formation state in the present invention;
6 is a view showing etching data of a comparative experiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated, referring drawings.

First, in FIG. 1, the substrate processing apparatus which implements this invention is demonstrated.

In FIG. 1, 1 denotes a substrate processing apparatus, 2 denotes a substrate storage container (cassette), and a substrate (wafer) 3 such as a silicon wafer processed by the substrate processing apparatus 1 is attached to the cassette 2. The required number of sheets, for example, 25 sheets, is carried in and out.

In the lower part of the front wall 5 of the box body 4 of the substrate processing apparatus 1, a front maintenance sphere 6 is formed as an opening for maintenance, and the front maintenance sphere 6 is a front maintenance tee. It can be opened and closed by a nonce door (not shown). Above the front maintenance port 6, a substrate storage container entrance / exit 8 for carrying in / out of the cassette 2 is established, and the substrate storage container entrance / exit 8 is an entrance / exit opening / closing mechanism (front shutter) ( (Not shown).

A substrate storage container receiving device (cassette receiving stage) 11 is provided inside the box body 4 and facing the substrate storage container inlet / outlet 8, facing the cassette receiving stage 11, and the cassette ( The lower plate storage container storage shelf (cassette shelf) 12 which stores 2) as needed, and the said plate storage container storage shelf (buffer cassette shelf) 13 are provided.

A substrate storage container conveyance apparatus (cassette conveyance apparatus) 14 is provided between the cassette delivery stage 11, the cassette shelf 12, and the buffer cassette shelf 13. The cassette conveying apparatus 14 includes a traversing mechanism, a lifting mechanism, and a rotating mechanism, and the cassette conveying apparatus 14 is formed by the cooperation of the transverse mechanism, the lifting mechanism, and the rotating mechanism, so that the cassette conveyance stage ( 11) the cassette 2 can be conveyed in a necessary posture between the cassette shelf 12 and the buffer cassette shelf 13.

A load lock chamber 15, which is an airtight container, is provided on the inner rear and the lower portion of the box body 4, and a processing furnace 16 is provided above the load lock chamber 15. The processing furnace 16 includes an airtight processing chamber 17, and the processing chamber 17 extends in an airtight manner with the load lock chamber 15, and a furnace section at the lower end of the processing chamber 17. ) Is hermetically closed by the furnace gate valve 20.

A substrate holder (boat) 18 can be accommodated in the load lock chamber 15, and the boat 18 is made of a heat resistant material such as quartz or silicon carbide, for example. It can be maintained in multiple stages in a horizontal position. In addition, it is preferable that the shelf supporting the wafer 3 be in a ring shape to be implanted. In the lower part of the boat 18, a plurality of heat insulating plates (not shown) as a heat insulating member made of a heat-resistant material such as quartz or silicon carbide (not shown) are arranged in a plurality of stages in a horizontal posture to radiate heat downward. Is suppressed.

In addition, a substrate holding device elevating mechanism (boat elevator) 19 for supporting the boat 18 and for attaching or detaching the boat 18 to the processing chamber 17 is provided in the load lock chamber 15. have.

The load lock chamber 15 is provided with a substrate movement mounting hole 21 for moving the wafer 3 to the boat 18, and the substrate moving mounting hole 21 is opened by a gate valve 25. And confidentially closed. A gas supply system 22 for supplying an inert gas such as nitrogen gas is connected to the load lock chamber 15, and an exhaust device (not shown) for exhausting the inside of the load lock chamber 15 to negative pressure is connected.

Between the load lock chamber 15 and the cassette shelf 12, a substrate movement mounting apparatus (substrate movement mounting apparatus) 23 is provided, and the substrate movement mounting apparatus 23 mounts and holds the wafer 3. The board holding plate 24 is provided with the required number of sheets (for example, five sheets), and is provided with a lifting mechanism unit for lifting and lowering the substrate holding plate 24, a rotating mechanism unit for rotating, and a retraction mechanism unit for advancing and retreating.

The substrate movement mounter 23 moves the substrate movement mounter 21 between the boat 18 and the cassette shelf 12 in the descending state by the cooperation of the elevating mechanism portion, the rotating mechanism portion, and the retraction mechanism portion. The substrate is moved and mounted.

In addition, a clean unit 26 is provided to face a required position inside the box 4, for example, the buffer cassette shelf 13, and the inside of the box 4 by the clean unit 26. The flow of clean atmosphere is formed.

Hereinafter, the operation of the substrate processing apparatus 1 will be described.

The substrate storage container entrance / exit 8 is opened by a front shutter (not shown), and the cassette 2 is carried in from the substrate storage container entrance / exit 8. The cassette 2 to be loaded is mounted in such a manner that the wafer 3 is in a vertical position, and the entrance and exit of the wafer 3 faces upward.

Next, the cassette conveying apparatus 14 is conveyed to the designated shelf position of the cassette shelf 12 or the buffer cassette shelf 13. The cassette 2 stored in the cassette shelf 12 and the buffer cassette shelf 13 is in a horizontal position, and the entrance and exit points toward the substrate moving mounter 23. In addition, after being temporarily stored, the cassette conveying apparatus 14 is moved and mounted from the buffer cassette shelf 13 to the cassette shelf 12.

The inside of the load lock chamber 15 is in an atmospheric pressure state, and the boat 18 is lowered into the load lock chamber 15 by the boat elevator 19. The substrate movement mounter 21 is opened by the gate valve 25, and the wafer 3 is moved from the cassette 2 to the boat 18 by the substrate movement mounter 23.

When a predetermined number of wafers 3 are loaded in the boat 18, the substrate movement mounting holes 21 are closed by the gate valve 25, and the load lock chamber 15 is evacuated by an exhaust device. The pressure is reduced by evacuation. When the load lock chamber 15 is decompressed at the same pressure as the pressure in the processing chamber 17, the furnace port portion of the processing chamber 17 is opened by the furnace port gate valve 20, and the boat elevator 19 opens the boat. 18 is charged in the processing chamber 17.

The wafer 3 is heated, the process gas is introduced into the process chamber 17, the exhaust is performed, and the wafer 3 is subjected to a predetermined process.

After the treatment, the boat 18 is drawn out by the boat elevator 19, and the gate valve 25 is opened after the inside of the load lock chamber 15 is restored to atmospheric pressure. Thereafter, the wafer 3 and the cassette 2 are carried out of the box body 4 in the reverse order to the above.

Next, the process furnace 16 and the boat elevator 19 are demonstrated in FIG.

As shown in FIG. 2, the said process furnace 16 has the heater 31 as a heating mechanism. The heater 31 has a cylindrical shape, is composed of a heater element line and a heat insulating member provided around the heater 31, and is vertically provided by being supported by a holder (not shown).

In the vicinity of the heater 31, a temperature sensor (not shown) as a temperature detector for detecting a temperature in the processing chamber 17 is provided. A temperature control unit 45 is electrically connected to the heater 31 and the temperature sensor, and adjusts the energization state of the heater 31 based on the temperature information detected by the temperature sensor. It is configured to control the temperature at a desired timing so that the temperature becomes a desired temperature distribution.

Inside the heater 31, a reaction tube 32 is provided concentrically with the heater 31. The reaction tube 32 is made of a heat resistant material such as quartz (SiO ₂ ) or silicon carbide (SiC), and is formed in a cylindrical shape in which the upper end is closed and the lower end is opened. The reaction tube 32 partitions the processing chamber 17, accommodates the boat 18, and the wafer 3 is stored in the processing chamber 17 while being held in the boat 18.

Below the reaction tube 32, the manifold 33 is provided concentrically with the said reaction tube 32, and the said reaction tube 32 is provided in the manifold 33 upright. The said manifold 33 consists of stainless steel etc., for example, and is formed in the cylindrical shape which the upper end and the lower end opened. In addition, an O-ring as a sealing member is provided between the manifold 33 and the reaction tube 32. Since the manifold 33 is supported by the holding body, for example, the load lock chamber 15, the reaction tube 32 is in a vertically installed state. The reaction vessel is formed by the reaction tube 32 and the manifold 33.

The gas manifold 33 is provided in the manifold 33 and the gas supply pipe 35 penetrates. The gas supply pipes 35 branch into three on the upstream side, and pass through the valves 36, 37, 38 and the MFCs 39, 40, 41 serving as the gas flow rate control device. It is connected to the gas supply source 43 and the 3rd gas supply source 44, respectively. The first gas supply source 42 supplies a silane gas or a halogen-containing silane gas as a process gas, and the second gas supply source 43 supplies a process gas or hydrogen gas as a carrier gas. The third gas supply source 44 is configured to supply nitrogen gas as a carrier gas or purge gas.

A gas flow rate control unit 46 is electrically connected to the MFCs 39, 40, 41 and the valves 36, 37, 38, and the gas flow rate control unit 46 has a desired flow rate of the gas to be supplied. It is comprised so that it may control at a desired timing so that it may become.

On the downstream side of the gas exhaust pipe 34, a vacuum exhaust device 48 such as a vacuum pump is connected via a pressure sensor as a pressure detector (not shown) and an APC valve 47 as a pressure regulator. As the vacuum exhaust device 48, a tertiary vacuum pump having a high exhaust capacity, for example, a molecular turbo pump + a mechanical booth, a pump + a dry pump, or the like is preferably used.

The pressure control part 49 is electrically connected to the pressure sensor and the said APC valve 47, The said pressure control part 49 is the opening degree of the said APC valve 47 based on the pressure detected by the pressure sensor. It is comprised so that the pressure of the said process chamber 17 may be controlled by desired timing so that the pressure of the said process chamber 17 may become predetermined pressure.

In the structure of the said process furnace 16, the 1st process gas is supplied from the said 1st gas supply source 42, and after the flow volume is adjusted to the said MFC 39, it passes through the said valve 36, It is introduced into the processing chamber 17 by the gas supply pipe 35. After the second processing gas is supplied from the second gas supply source 43 and the flow rate of the MFC 40 is adjusted, the processing chamber 17 is provided by the gas supply pipe 35 via the valve 37. ) Is introduced. After the third processing gas 1 is supplied from the third gas supply source 44 and the flow rate thereof is adjusted by the MFC 41, the processing chamber 1 is supplied from the gas supply pipe 35 via the valve 38. It is introduced in 17. In addition, the gas in the processing chamber 17 is exhausted from the processing chamber 17 by the vacuum exhaust device 48 connected to the gas exhaust pipe 34.

Next, the boat elevator 19 will be described.

The drive mechanism 51 of the boat elevator 19 is provided on the side wall of the load lock chamber 15.

The drive mechanism 51 includes a guide shaft 52 and a ball screw 53 which are installed in parallel, and the ball screw 53 is rotatably supported and is rotated by a lifting motor 54. . A lifting table 55 is slidably fitted to the guide shaft 52 and screwed to the ball screw 53, and the lifting table 55 has a hollow lifting shaft parallel to the guide shaft 52. 56) is installed down.

The lifting shaft 56 freely penetrates the ceiling surface of the load lock chamber 15 and extends therein, and a hollow drive part storage case 57 is hermetically installed at a lower end thereof. A bellows 58 is provided to cover the lifting shaft 56 in a non-contact manner, and an upper end of the bellows 58 is located on a lower surface of the lifting table 55, and a lower end of the bellows 58 is mounted on the rod. It is hermetically fixed to the upper surface of the lock chamber 15, respectively, and the free passages of the lifting shaft 56 and the lifting shaft 56 are hermetically sealed.

In the ceiling of the load lock chamber 15, a furnace port 59 is provided concentrically with the manifold 33, and the furnace port 59 is hermetically closed by a seal cap 61. The seal cap 61 is made of, for example, a metal such as stainless steel, is formed in a disk shape, and is hermetically fixed to an upper surface of the drive part storage case 57.

The drive part storage case 57 has an airtight structure, and the interior thereof is isolated from the atmosphere in the load lock chamber 15. The boat rotating mechanism 62 is installed inside the driving unit storage case 57, and the rotating shaft of the boat rotating mechanism 62 passes freely through the ceiling plate of the driving unit storage case 57 and the seal cap 61. Extends upward, the boat mount 63 is fixed to the upper end, and the boat 18 is mounted on the boat mount 63.

The seal cap 61 and the boat rotating mechanism 62 are respectively cooled by water-cooled cooling mechanisms 64 and 65, and the cooling water pipe 66 for the cooling mechanisms 64 and 65 is the lifting shaft ( 56 is connected to an external cooling water source (not shown). In addition, the power supply to the boat rotating mechanism 62 is performed via a power supply cable 67 wired through the lifting shaft 56.

A drive control unit 68 is electrically connected to the boat rotating mechanism 62 and the lifting motor 54, and is configured to control at a desired timing so as to perform a desired operation.

The temperature control part 45, the gas flow rate control part 46, the pressure control part 49, and the drive control part 68 also comprise an operation part and an input / output part, and a main control part that controls the entire substrate processing apparatus 1. It is electrically connected to (69).

As described above, the driving unit of the boat elevator 19, the boat rotating mechanism 62, the cooling water pipe 66, the power supply cable 67 and the like are the driving unit housing case 57, the bellows ( 58 is isolated from the inside of the load lock chamber 15, so that the drive system and the wiring system by the heat generated when the load lock chamber 15 is evacuated or when the furnace gate valve 20 is opened. The wafer 3 is not contaminated by organic matter and particles generated from the particles.

Next, a method of forming a film on a substrate such as the wafer 3 as one step of the manufacturing process of the semiconductor device using the processing furnace 16 will be described with reference to FIG. 3.

In addition, in the following description, the operation | movement of each part which comprises the said substrate processing apparatus 1 is controlled by the said main control part 69. FIG.

First, the native oxide film on the surface of the wafer 3 is removed with hydrofluoric acid, and the surface is hydrogen terminated at the same time (step: 01).

The boat 18 is lowered by the boat elevator 19, and the furnace port 59 is hermetically closed by the furnace port gate valve 20. The substrate moving mounting hole 21 is opened by the gate valve 25 in a state in which the inside of the load lock chamber 15 is equalized with the outside of the load lock chamber 15. A predetermined number of wafers 3 are loaded into the boat 18 by the substrate movement mounting tool 23 (step: 02).

The substrate movement mounting hole 21 is hermetically closed by the gate valve 25, and the inside of the load lock chamber 15 is repeatedly vacuumed and purged with an inert gas (for example, nitrogen gas), Oxygen and moisture in the atmosphere inside the load lock chamber 15 are removed.

Next, the furnace port 59 is opened by the furnace port gate valve 20, and the boat elevator 19 is driven. The ball screw 53 is rotated by the driving of the lifting motor 54, the driving unit storage case 57 is raised via the lifting table 55 and the lifting shaft 56, and the boat 18 is It is charged to the said process chamber 17. In this state, the seal cap 61 hermetically closes the furnace port 59 via an O-ring.

In addition, in order to prevent surface oxidation of the wafer 3, the temperature of the said process chamber 17 at the time of charging is made into 200 degreeC or 200 degreeC vicinity (step: 03).

The process chamber 17 is evacuated by the vacuum exhaust device 48 so as to achieve a desired pressure (vacuum degree). At this time, the pressure in the processing chamber 17 is measured by a pressure sensor, and the APC valve 47 is feedback controlled based on the measured pressure. In addition, the processing chamber 17 is heated by the heater 31 so as to have a desired temperature and a desired temperature distribution, and the heating state is feedback-controlled by the temperature controller 45 based on the temperature information detected by the temperature sensor. . Subsequently, the boat 18 is rotated by the boat rotating mechanism 62 to rotate the wafer 3.

The boat 18 is charged into the processing chamber 17, and when the exhaust is completed, the pretreatment temperature (usually the same as the deposition temperature. H ₂ When processing only with gas, it is 750-800 degreeC. After the boat is charged, the process of raising the temperature is also possible), and pretreatment is performed. The pretreatment includes hydrogen gas or silane-based gas (eg, from the first gas supply source 42, the second gas supply source 43, and the third gas supply source 44 through the MFCs 39, 40, and 41). For example, SiH ₄ ), halogen-containing silane gas, hydrogen chloride gas, or a combination of these gases is supplied together with a carrier gas such as an inert gas or hydrogen gas (step: 04).

By performing pretreatment, interfacial oxygen and carbon density can be reduced, and a high quality interface can be formed between a semiconductor substrate and a thin film.

When the pretreatment is completed, the residual gas in the processing chamber 17 is removed by a carrier gas such as hydrogen.

The temperature of the said processing chamber 17 is temperature-controlled from pretreatment temperature to film-forming temperature. At this time, hydrogen gas is flowed into the processing chamber 17 as a carrier gas to prevent contamination by back diffusion from the exhaust system (step: 05).

When the temperature of the processing chamber 17 is stabilized at the film forming temperature, the processing gas is introduced to form the film. Process gases are supplied from the first gas supply source 42, the second gas supply source 43, and the third gas supply source 44. In addition, after the opening degree of the MFCs 39, 40, 41 is adjusted to achieve a desired flow rate, the valves 36, 37, 38 are opened, and each processing gas flows through the gas supply pipe 35. It is introduced into the process chamber 17 from the upper part of the process chamber 17.

As the processing gas to be introduced, a silane gas (SiH ₄ ), a halogen gas containing gas, a silane gas mixed with hydrogen gas, or a halogen containing silane gas mixed with hydrogen gas is used. When the processing gas is SiH ₄ , the film formation temperature in the processing chamber 17 is adjusted to 500 to 700 ° C.

The introduced process gas is exhausted from the gas exhaust pipe 34 through the process chamber 17. The processing gas comes into contact with the wafer 3 when passing through the processing chamber 17, and an EPI film grows on the surface of the wafer 3 and is deposited (deposited). In addition, unnecessary nuclei on the insulating film are removed by etching. The film formation and etching are repeated a predetermined number of times to produce a predetermined film (step 06).

When a predetermined time elapses, an inert gas is supplied from an inert gas supply source (not shown), the process chamber 17 is replaced with an inert gas, and the pressure in the process chamber 17 is returned to normal pressure [ Equalize with the inside of the load lock chamber 15] (step: 07).

Thereafter, the processing chamber 17 is lowered to a temperature at which the surface of the wafer 3 is not oxidized, for example, 200 ° C (step: 08).

The seal cap 61 is lowered by the boat elevator 19 so that the furnace port 59 is opened and at the same time the boat 18 is carried out from the furnace port 59 into the load lock chamber 15. The furnace port 59 is closed by the furnace port gate valve 20. After the wafer 3 is cooled in the load lock chamber 15 to the required temperature, the substrate movement mounting hole 21 is opened, and the processed wafer 3 is transferred to the substrate movement mounting machine 23. By the boat 18 (see Fig. 1) (step 09).

An example of the film forming step of step 06 is described with reference to FIGS. 4A and 4B.

First, FIG. 4A shows a first film forming step, and shows the case where Cl ₂ is introduced using N ₂ as a carrier gas when etching is performed.

First, SiH ₄ and H ₂ are introduced to form a film (step 11).

By simultaneously introducing SiH ₄ and H ₂ , the treatment chamber 17 is kept clean, and SiH ₄ is decomposed into Si + 2H ₂ , but the presence of H ₂ introduced at the same time suppresses the decomposition. In other words, by introducing SiH ₄ and H ₂ simultaneously, the decomposition degree of SiH ₄ can be controlled.

Thereafter, SiH ₄ is removed from the processing chamber 17 by the H ₂ purge (step 12). H ₂ The purge removes the processing gas and simultaneously terminates the substrate surface.

Next, nitrogen gas is introduced to purge the N ₂ (step 13), and then Cl ₂ and N ₂ are introduced to remove (etch) unnecessary nuclei on the insulating film (step 14). Next, N _{2 is} purged to remove Cl ₂ from the process chamber 17 (step 15), H _{2 is} purged again, and N ₂ is removed (step 16).

Repeat steps 11 to 16 to produce the required membrane.

In addition, in the case of producing the impurity diffusion film, PH ₃ , B ₂ H ₆ , BCL ₃ in the middle of the above steps: 11 to 16: Doping gases, such as these, are introduce | transduced.

In this step, since SiH ₄ is used as the film forming gas, the film forming temperature can be set at a low temperature of 500 to 700 ° C, and the effects of thermal damage and thermal budget on the substrate element can be reduced. In the case of using Si ₂ H ₆ as the film forming gas, the film forming temperature can be set at a lower temperature than that in the case of using SiH ₄ at 450 to 700 ° C.

Next, FIG. 4B shows a second film forming step example, and shows the case where Cl ₂ is introduced using H ₂ as a carrier gas when etching is performed.

First, SiH ₄ and H ₂ are introduced to form a film (step 21). In this case, SiH ₄ Gas flow rates of 100 to 500 sccm, H ₂ gas flow rates of 100 to 20000 sccm, processing temperatures of 500 to 700 ° C, and processing pressures of 1000 Pa or less are preferable.

Controlling the decomposition state of SiH ₄ by introducing SiH ₄ and H ₂ simultaneously is the same as described with reference to FIG. 4A.

Thereafter, SiH ₄ is removed from the process chamber 17 by H ₂ purge (step 22). The H ₂ purge removes the processing gas and terminates the substrate surface by H.

Cl ₂ and H _{2 are} then introduced to remove (etch) unnecessary nuclei on the insulating film (step 23). In this case, a Cl ₂ gas flow rate of 50 to 200 sccm, a H ₂ gas flow rate of 100 to 20000 sccm, a treatment temperature of 500 to 700 ° C, and a treatment pressure of 1000 Pa or less are preferable.

Next, H ₂ purge to remove Cl ₂ (step 24). In etching, since Cl ₂ is diluted with H ₂ , the uniformity of etching is increased.

Repeat steps 21 to 24 to produce the required membrane.

In addition, in the case of producing the impurity diffusion film, PH ₃ , B ₂ H ₆ , BCl ₃ in the middle of the above steps: 21 to 24: Doping gases, such as these, are introduce | transduced.

In addition, depending on the production conditions of the film, in the gas introduction process in the step: 21, step: 23, SiH ₄ , Cl ₂ , H ₂ The flow rate of one or more gases is changed.

For example, by increasing the amount of SiH ₄ , the deposition rate is increased, and by increasing the amount of Cl ₂ , the etching amount is increased. Therefore, the following forms are attained by changing gas flow volume.

For example, SiN has a characteristic that nuclei of Si are easily grown, and Si nuclei is difficult to grow. Therefore, for example, in a substrate in which an insulating film (SiO) is formed over the insulating film SiN and the cross-sections of both insulating films are exposed (see Fig. 5), the film formation process is performed with a strong etching degree (low film formation speed) at the beginning. When the film thickness exceeds the thickness of the SiN, the etching rate can be reduced to increase the film formation speed.

For example, if an Si surface to be formed into a film has an impurity, the film is polycontained. Therefore, the initial stage of growth increases the etching degree and removes the impurity, and when the EPI film is formed to some extent, the etching degree is weakened. Speed up film formation.

In addition, by increasing the processing pressure, the etching and film forming functions are increased, and the above-described form is also obtained by changing the processing pressure in the film forming process.

In the second film forming step, since SiH ₄ is used as the film forming gas, the film forming temperature can be set at a low temperature of 500 to 700 ° C., and the effects of thermal damage and thermal budget on the substrate element can be reduced. In the case of using Si ₂ H ₆ as the film forming gas, the film forming temperature can be set to 450 to 700 ° C. and lower than that of SiH ₄ .

In addition, in the second film forming step, since Cl ₂ and H ₂ are introduced into the processing gas in the etching, there is no need to purge N ₂ before and after the etching step, and the N ₂ purge step can be omitted, and the film forming step is performed. The process can be simplified and the processing time can be shortened, thereby improving throughput.

In addition, the uniformity of the film formation in the first film forming step is about 20%, and the uniformity of the film forming in the second film forming step is obtained by 5 to 10%, and in the second film forming step example, as compared with the first film forming step. The improvement of the film-forming quality was obtained.

When the etching using a Cl ₂ with respect to a monitor wafer film Poly-Si in FIG. 6, the etching rate, and wafer in-plane uniformity of the etching amount in the case with the case of using N ₂ and H ₂ as a carrier gas The results of the experiments are compared.

In this FIG. 6, ▲, (circle) represent an etching rate, (triangle | delta) and (circle) represent etching amount wafer in-plane uniformity.

As experimental conditions, the following conditions were performed.

Treatment temperature: 620 ℃

Voltage: 2 Pa

Cl ₂ partial pressure: 0.04 Pa

N ₂ Partial Pressure: 1.96 Pa

H ₂ partial pressure: 1.96 Pa

Table 1 shows each value obtained by the experiment under the above conditions. From these results, as the carrier gas side of the etching with the case of using H ₂ as a carrier gas than the etching with the case of using N _2, a low etching rate, it can be seen that a good in-plane uniformity of the etching amount. Therefore, it can be said that the end of the etching with the case of using H ₂ as a carrier gas, to improve the uniformity of the deposition.

In addition, it can be seen that the side of the road can be etched using as a carrier gas in the case of using H ₂ 6 also improved gender wafers uniformly.

When using N ₂ When using H ₂ Etching Rate [mm / min] 12-16 10-12 Etching amount In-plane uniformity [%] To ± 10 To ± 5

Next, when etching is performed using Cl ₂ as an etching gas, the reason why the etching uniformity is improved in the case where H ₂ is used as the carrier gas is improved compared to the case where N ₂ is used as the carrier gas. .

In the case where etching is performed using only Cl ₂ without using a carrier gas, or when etching using N ₂ as a carrier gas, etching of Cl ₂ becomes dominant. Therefore, the etching of the edge portion of the wafer becomes stronger and the gas is consumed at the edge, so that the etching gas does not reach the center of the wafer and the uniformity decreases.

On the other hand, when H ₂ is used as the carrier gas, Cl ₂ and H ₂ react in a gaseous phase to form an intermediate, whereby a reaction in which 2HCl is formed occurs in part, and the etching force is lowered. Since the intermediate of HCl is formed in the process, etching gas can reach the center of a wafer, and it is thought that uniformity improves.

Moreover, since the etching effect of Cl falls because H is coat | covered on the wafer surface, it also becomes one of the reasons that the amount of gas which reaches the center of a wafer increases.

In the case where etching is performed using H ₂ as the carrier gas, the reason why using Cl ₂ as the etching gas is more effective than using HCl as the etching gas will be described.

Since the treatment furnace 16 has a hot wall structure, it is etched by gas decomposed in the gas phase. However, since HCl takes a long time to decompose in a low temperature treatment like the present application, it becomes difficult to secure selectivity. On the other hand, Cl ₂ is because the thermal decomposition proceeds rapidly even at low temperature processes, the side of the Cl ₂ etch rate is increased, it is possible to ensure a more selective.

Then, the relationship between the etching force when hayeoteul diluted with H ₂ is not changed, since the etching power than when one is using HCl as an etching gas in the case of using Cl ₂ stronger as the etching gas, with Cl ₂ as the etching gas, In this case, good results can be obtained in the low temperature treatment as described herein.

In addition, since the reaction that the intermediate of HCl is generated in the gas phase by heat occurs, the uniformity of film formation can be improved by using Cl ₂ as the etching gas and H ₂ as the carrier gas as described above. Therefore, the effect of this invention is achieved because it is a hot wall structure which heats the atmosphere in a reaction tube.

In addition, in the above embodiment, the formation of the EPi-Si film on the substrate has been described, but the present invention also applies to a single crystal film, a polycrystalline film, an amorphous film, or the like, or a doped single crystal film, a polycrystalline film, an amorphous film, or the like. It is possible to implement.

Moreover, the substrate processing apparatus which this invention is implemented can be implemented in the board | substrate processing apparatus generally, such as a horizontal type substrate processing apparatus, for example, can also be implemented also in a single wafer type hotwall type substrate processing apparatus.

(bookkeeping)

In addition, the present invention includes the following embodiments.

(Supplementary Note 1) In the method of manufacturing a semiconductor device in which a thin film is selectively formed on a silicon substrate by a reduced pressure CVD method (chemical vapor growth method), SiH ₄ Silane gas such as silane gas and Cl gas such as Cl ₂ are alternately and intermittently supplied together with hydrogen gas to grow a thin film having a high quality interface, and a silicon film or silicon on an insulating film such as a silicon nitride film A method for manufacturing a semiconductor device, characterized by maintaining selectivity without growing nuclei.

(Supplementary Note 2) SiH ₄ in the middle of the repetitive cycle shown in Supplementary Note 1; Silane gas such as Cl ₂ A method of manufacturing a semiconductor device for changing a gas flow rate of at least one of halogen-based gas and hydrogen gas.

(Supplementary Note 3) A method for manufacturing a semiconductor device, wherein the pressure in the reactor is changed during the repeated cycles shown in Supplementary Note 1 and Supplementary Note 2.

(Supplementary Note 4) During the repetitive cycle shown in Supplementary Note 1, Supplementary Note 2, and Supplementary Note 3, PH ₃ , B ₂ H ₆ , BCl ₃ A method of manufacturing a semiconductor device for introducing a doping gas such as the above.

(Supplementary Note 5) In any one of Supplementary Note 1, Supplementary Note 2, and Supplementary Note 3, when the silicon substrate and the silicon substrate processing jig (boat) are introduced into the reactor in the front of the reactor, the drive shaft part And a boat rotating mechanism portion and a wiring portion isolated from the entire chamber of the reactor.

While the embodiments of the present invention have been described above, it will be understood by those skilled in the art that the present invention is not limited thereto and that various changes and modifications can be made without departing from the spirit and scope of the appended claims. shall.

Claims (9)

A substrate having at least a silicon surface and an insulating surface on its surface is housed in a processing chamber,
Fabrication of a semiconductor device for selectively growing an epitaxial film on a silicon surface of the substrate using a substrate processing apparatus for heating the atmosphere in the processing chamber and the substrate to a predetermined temperature by a heating unit provided outside the processing chamber. In the method,
Carrying in a substrate into the processing chamber;
Heating the atmosphere in the processing chamber and the substrate to a predetermined temperature;
A gas supply and distribution step of supplying and supplying a predetermined gas to the processing chamber,
The gas supply and distribution process,
A first supply step of supplying silicon-containing gas and hydrogen gas from the peripheral edge portion of the substrate of the processing chamber toward the center of the substrate;
A first removing step of removing at least the silicon-containing gas from the processing chamber;
A second supply step of supplying chlorine gas and hydrogen gas from the peripheral edge portion of the substrate of the processing chamber toward the center of the substrate;
A second removal step of removing at least said chlorine gas from said processing chamber,
And repeating the gas discharging step a predetermined number of times to selectively grow an epitaxial film on the silicon surface of the substrate. The method of claim 1,
The gas supply / discharge step further includes a third supply step of supplying a doping gas to the processing chamber. The method of claim 1,
And in the gas discharging step, supplying to the processing chamber while varying the flow rates of at least one of the silicon-containing gas, the chlorine gas, and the hydrogen gas. The method of claim 1,
A predetermined number of times, after repeating the gas supply / discharge process, at least the flow rate of the chlorine gas is reduced, and the gas supply / discharge process is repeated the predetermined number of times. The method of claim 1,
A predetermined number of times, after repeating the gas supply / discharge process, at least the flow rate of the silicon-containing gas is increased and the gas supply / discharge process is repeated a predetermined number of times. The method of claim 1,
A predetermined number of times, after repeating the gas supply / discharge process, at least the flow rates of the silicon-containing gas and the chlorine gas are increased and the gas supply process is repeated a predetermined number of times. The method of claim 1,
And in the gas supply and discharge step, a pressure in the processing chamber is varied. Using a substrate processing apparatus that accommodates a substrate having at least a silicon surface and an insulating surface on its surface in a processing chamber, and heats the atmosphere in the processing chamber and the substrate to a predetermined temperature by a heating unit provided outside the processing chamber. In the film generating method for producing a film on the substrate,
Carrying in a substrate into the processing chamber;
Heating the atmosphere in the processing chamber and the substrate to a predetermined temperature;
A gas supply and distribution step of supplying and supplying a predetermined gas to the processing chamber,
The gas supply and distribution process,
A first supply step of supplying silicon-containing gas and hydrogen gas from the peripheral edge portion of the substrate of the processing chamber toward the center of the substrate;
A first removing step of removing at least the silicon-containing gas from the processing chamber;
A second supply step of supplying chlorine gas and hydrogen gas from the peripheral edge portion of the substrate of the processing chamber toward the center of the substrate;
A second removal step of removing at least said chlorine gas from said processing chamber,
And generating a film on the substrate by repeating the predetermined number of times. At least silicon-containing gas and chlorine gas,
A substrate processing apparatus for growing a film on a surface of a substrate accommodated in the processing chamber by alternately repeating the silicon-containing gas and the chlorine gas alternately.
A processing chamber accommodating a substrate,
A heating unit installed outside the processing chamber and heating the substrate and the atmosphere in the processing chamber;
A gas supply unit for supplying a predetermined gas into the processing chamber from the peripheral edge portion of the substrate toward the center of the substrate;
An exhaust port opening in the processing chamber;
A control unit for controlling at least the heating unit and the gas supply unit,
The gas supply unit,
A first gas supply member for supplying a silicon-containing gas;
A second gas supply member for supplying chlorine gas;
Having a third gas supply member for supplying hydrogen gas,
The control unit,
The gas supply unit is configured to supply hydrogen gas toward the central portion of the substrate from the peripheral edge portion of the substrate in the processing chamber while supplying the silicon-containing gas toward the central portion of the substrate from the peripheral edge portion of the substrate in the processing chamber. Control,
Controlling the gas supply unit to supply hydrogen gas from the peripheral edge of the substrate in the processing chamber toward the center of the substrate at the same time when the chlorine gas is supplied from the peripheral edge of the substrate in the processing chamber toward the central portion of the substrate; Substrate processing apparatus, characterized in that.

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