TWI281199B - Method and apparatus for shaping thin films in the near-edge regions of in-process semiconductor substrates - Google Patents

Abstract

An atmospheric plasma source is employed as a source of chemically active gaseous species. The chemically active gaseous species so generated are directed towards the near-edge surfaces of in-process semiconductor substrates via gas flow control devices and electro-mechanical positioning devices. Informed selection of the plasma source input gases allows the skilled practitioner to tailor the performance of the output chemistry to achieve either material removal or material deposition. Shaping of the substrate removal or deposition process is achieved by controlling the relative motion between the substrate and the plasma source.

Description

1281199 _ case number 92109291_年月曰__, five, invention description (1) Technical Field of the Invention The present invention relates to a method and apparatus for forming a thin film on a semiconductor substrate in a process, and more particularly to a use of electricity A method and apparatus for forming a film in the near-edge regions of a semiconductor substrate during the process. [Prior Art]

• The future tends to require manufacturing engineers in the integrated circuit (IC) manufacturing process to clarify the root cause of contamination. In 1 (] Manufacturing Engineering, an emerging sensing system confirms that the edge exclusion area and edge surface of the substrate are The source of contamination. The problem of contamination from these marginal areas is the result of insufficient film adhesion resulting in thinning of the film and detachment from the surface; if such loose film fragments or sheets are moved to form The center position of the active component's wafer will turn into a fatal defect. The current method of removing the peeling film (edge water droplet removal EBR) is also a problem, and the removal method in the near-edge terrain is difficult to remove and SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a relatively simple technique for removing exfoliated films during wafer fabrication. Another object of the present invention is to control film formation in a process. Medium wafer

on. Another object of the present invention is to provide an economical technique for forming wafer edges in a process. > Briefly stated, the present invention provides a method of forming a film on a wafer: and apparatus.

Page 5 1281199 __ Case No. 92109291_年月曰> Correction _, V, invention description (2) The device of the present invention uses a rotating base to hold a wafer, and a housing having a narrow hole for receiving At the edge of the wafer on the susceptor, at least one plasma source is disposed on the outer casing to generate a large amount of reactive gas, and a passage is located in the outer casing and communicates with the plasma source, so that a large amount of reactive gas can be directly located. The edge of the wafer in the elongated hole of the case. In addition, the present invention discloses an exhaust space (^ exhaust plenum) located in the outer casing to accommodate the reactive gas, and another exhaust line connected and extended by the exhaust space so that the exhaust space will react Sexual gas ~ body discharge. Moreover, at least one additional channel is located in the housing and radially in the first channel to direct a dilution/cooling gas flow to the wafer; and at least one exhaust channel is located in the housing and Located between the additional passage and the first passage to discharge the dilution/cooling gas and the reactive gas therefrom. Typically, the outer casing is semi-circular to receive a major portion of the wafer on the pedestal so that it lies within the elongated aperture, but the outer casing may be of other suitable shape. The device is also composed of a plurality of sets of inlet channels, exhaust channels and a plurality of plasma sources. For example, three plasma sources are respectively located around the outer casing to selectively etch the polymer on the wafer and etch the crystal. The ruthenium dioxide on the circle and a layer of ruthenium dioxide deposited on the wafer. The method of the present invention comprises the steps of: disposing a wafer having a film on a rotating pedestal; directing a dilution/cooling gas to radially flow to the crystal/circle; and discharging the dilution/cooling gas flowing out of the wafer Downflow dilution / : cooling gas; directing a reactive gas to the wafer and flowing radially

1281199 __Case No. 92109291_年月日日_^_, V. Description of invention (3) Dilution/cooling gas to react reactive gas with the wafer; and rotating the wafer to remove the flow using reactive gas Film fragments on the edge of the wafer or a material deposited on the wafer. During the rotation, the wafer is moved in a linear direction, and the material on the wafer film is removed by the flow of the reactive gas to form the film into a predetermined shape; after that, the reactive gas is guided to flow to the wafer a second time. And radially flowing out the dilution/cooling gas, causing the reactive gas to react with the wafer to deposit a material thereon, and rotating the wafer to utilize the second flow of the reactive gas to crystallize A protective film is deposited on the round formed film. The process capabilities of the apparatus and methods described herein complete the removal of the exfoliated film and control the shape of the film after the process, which allows for the use of conventional cleaning processes without particle trapping. Moreover, the process can also encapsulate a film on the surface of the wafer in the process to prevent future peeling. According to the present invention, the semiconductor substrate (wafer) is placed on a pedestal in a process (for example, using a vacuum) The diameter of the pedestal is sufficiently smaller than the wafer diameter to allow access to all wafer edge surfaces. The base is attached with a rotating shaft which is connected to a rotating electromechanical system. In the manufacturing process, the electromechanical system controls the rotational movement of the wafer by a computer; in addition, the entire base unit is mounted on a 3-axis (X , Υ, Ζ) on a linear mechanical positioning device. The plasma source is located close to the edge surface of the wafer, as described in U.S. Patent No. 5,9, 2,7,7 2; by gas flow hardware design and electromechanical positioning devices (X, Υ k and 2 crystals) The circular moving axis), the flowing gas generated from the plasma source (flame) will be straight: it will hit the edge surface.

1281199 Rev. 92109291 Revised. 5. V. INSTRUCTIONS (4) Choosing the appropriate input gas will determine the type of process completed on the wafer. Certain gas mixtures will result in material and flame composition on the wafer. The reaction forms a volatile by-product under operating pressure, which in this example is reduced and generally refers to the remainder. Other input gas mixtures will cause the flame composition to react with each other to deposit a material on the wafer. In this example, the process is increased and is generally referred to as chemical vapor deposition (CVD). Use the set bit. A system of control and control of the surface of the surface of the equipment is fixed to the edge of the machine circular machine crystal and the helium gas If- rnj. The control should be controlled when the time required to stay in the stop for a long time The command will kill the flame, the fire on the domain, the shape of the zone, the shape of the material, the material of the material, the shape of the material, the need for the film, the C C thin, the thickness of the area, the When moving the material, the length of the material is less than the body, and the gas will be fired. The short-lived gas will be ordered and the film will be replaced. In the case of the side of the zone, the JIL and the domain system are in the process of saying that the § is the most important thing to do. The finite period of the system of the divergent zone of the analytic domain is used to pre-plant the non-one-moving process to raise the body of the body, but the body is cold or thin, and the circle is used by the crystal, from the external gas to the anti-scattering cold diffusion or domain. It can be adjusted by the section of the valve, and the section of the area of the map is attached to the pre-matched non-exemplary. The achievement of the merits and the point of the special \ The effect of the figure is shown in Figure F 11 to the figure] A r1 type of the first test to participate in the removal of the drip edge C. B - one species

Μ 1

Page 8 1281199 Case No. 92109291 修正 Amendment 5. Invention Description (5) The conventional technique of bead removal (EBR) often occurs in a shape near the edge of a wafer and is not easily removed and trapped in particles. In the conventional art, there is a cover layer 11 of any suitable material on the wafer 10, as shown, the fragments 12 may be broken by the formed film peeling. Next, as shown in FIG. 1B, a photoresist layer 13 is formed. After exposing the photoresist layer 13 using conventional techniques as shown in FIG. 1C, the cover layer 11 and the debris 12 at the periphery of the wafer 10 are exposed as shown in FIG. The cover layer 1 1 and the debris 1 2 located around the periphery of the wafer 10 are then removed using a wet or dry film etching step, as shown in Figure 1E (which depicts a wet I insect rim). Finally, the photoresist layer 13 is stripped to clean the surface as shown in Fig. 1F. However, the end region of the cover layer 11 on the wafer 10 is trapped in the small particles 14. Referring to Figures 2A, 2B, and 2C, the present invention provides a method of processing a wafer as shown in Figure 2A, which removes the exfoliated film fragments and forms the remaining film shape, such as Figure 2B. As shown, the peripheral edge of the cover layer 1 is radially outwardly tapered to interface with the outermost periphery of the wafer 10. Thereafter, as shown in Fig. 2C, the surface of the treated cover layer 1 is sealed by a film 15 . Referring to FIG. 3, a wafer 10 is placed on a vacuum chuck 1 6 Ji, which can move horizontally along the X-axis and the Y-axis, or vertically along the Z-axis; in addition, the vacuum The base 16 is equipped with a rotating shaft (9, shown in Figure 7. This vacuum base is usually combined in an electromechanical system with suitable means (not shown) so that the vacuum base 16 is here. Move in 4 degrees of freedom ^ (X, Y, Z, and 0). : Referring to Figure 3, the three plasma sources 17t, 17e, and 17b are located respectively.

Page 9 1281199 Case No. 92109291 曰 Amendment 5, Invention Description (6) The top, side and bottom of the near wafer 1 以 to provide reactive gas flow to the three surfaces of the wafer 1 , the composition of each plasma source Atmospheric pressure plasma jets as described in U.S. Patent No. 5,961,772, the arrangement of the three plasma sources provides maximum flexibility in process selection, as described below: Top 10, bottom surface of wafer 10 And a separate process on the side; a synchronous process of any of the aforementioned surfaces of the wafer 10; and a simultaneous process of all three surfaces of the wafer 10. Referring to Figures 3 and 5, a pair of flow channels 19 and 20 are connected to each of the plasma sources 17 to control the excess diffusion of the reactive gas to the portion of the wafer 10 which is not used in the process. Channel 19 provides a dilute or cooled gas flow to the center of wafer 10 and radially outward toward wafer 10 edge; elongated exhaust channel 20 regulates gas flow from wafer 10 to the outside flow. The tuned conductive control valve 21 is used to adjust the flow rate of the dilute or cooling gas suitable for use in the passage 19. The reactive gas system from the plasma source 17 and diffused to the center of the wafer 10 is neutralized and carried away by the gas stream and exits through the exhaust passage 20; this technique can be between the treated and untreated regions Form a sharp border. Referring to Figures 3 and 4, the plasma source 17 is mounted on a semi-circular housing 18, and the housing 18 includes a slot 22 for receiving the wafer 10, as shown in Figure 3. The outer casing 18 is equal to or approximately equal to the size of the wafer 10 - half. The housing 18 also includes an exhaust space 23 that is coupled to an exhaust source (not shown) via an adjustable pilot control valve 24. The fourth figure illustrates a schematic diagram of three sets of plasma source 17 , a cooling gas passage 19 and an exhaust "conductive control valve 2 1 & 2 4 arranged in a housing 18, the arrangement of each group: Their respective process chemistries work independently. For example, a group can be used to enter

Page 10 1281199 _ Case No. 92109291 V. Description of the invention (7) Year 曰 Correction of the setting of the etching polymer, such as 1 7 ', 1 9 ', 2 Γ and 2 4 '; another set for etching The setting of cerium oxide (S i 0 2 ) is indicated as indicated by 1, 7 , 1 9 , 2 1 and 2 4 ; the third set is used to deposit a layer of cerium oxide layer, as indicated by 1 7 n , 1 9 π , 2 1π and 2 4 π are shown. An example of a process is shown in Table 1, where the first row contains the input gas, the second row contains the active output species, the third row contains the type of process performed, and the fourth row contains the film locations where the process takes place. - Table 1 Input gas y Active output type ♦ Process type p film p He, CF4, 〇2^ Fluorine atom p etched Si Si, Si02, Si3N4, 'W/Ta^ He, Oy 氡 atom p etch y organic polymer p He,03, TEOS<(O-Si-O)*^ deposition (CVD), Si02^

Generally, a continuous step of forming a hafnium oxide film on the top surface of a wafer is performed by a ceria chemical vapor deposition (CVD) encapsulation process as shown in Figs. 2A, 2B, and 2C, as described in detail below. : 1. Place a good center wafer 10 on a vacuum wafer base 16. 2. The vacuum wafer pedestal 16 moves on the X, Y, and Z axes such that the wafer 10 is located at the center of the elongated hole 22, and the edge portion of the wafer is located adjacent to the dilution/cooling gas supply channels 19t and 19b. s position.

3. Transfer the flow rate setpoint of the dilution/cooling gas to mass flow controllers (MFC) 25t and 25b and command the dilution/cooling gas shut-off valve to open 6 6 t and 2 6 b; the gas begins to flow The full dilution/cooling gas supply channel is 1 9 t and 1 9 b, and strikes the wafer 10 edge.

Page 11 1281199 _ Case No. 92109291_年月日日_ί±^_> V. Description of the invention (8) 4. Command the elongated exhaust passage conductive control valve 2 1 t to open to a predetermined position. (The conductive control valve 2 1 b is not opened so that the dilution/cooling gas does not flow out from the channel 19 b to protect the back side of the wafer 10 from unwanted reactive gases). 5. The process gas flow rate set value is transmitted to the mass flow controller of the process input gas (not shown), and the process input gas shutoff valve 2 71 is commanded to open; the process input gas 氦 (He), oxygen ( 02 ) and Carbon tetrafluoride (CF4) begins to flow through the channel 30t. 6. Command the housing venting space 2 3 of the conductive control valve 2 4 to open to a predetermined position.

7. Transfer a power supply setting to the RF power supply 2 9 t and command the RF power to turn on. The plasma and reactive gas formed in the plasma source 71 begins to flow through the passage 3 0 t into the outer casing exhaust space 2 3 and flows out of the conductive control valve 24 to the exhaust system (not shown) 〇 8 --- Impedance matching

n e t w o r k ) 2 8 t adjusts the load impedance to suit the output impedance of the RF power supply 2 9 t. The control system (not shown) compares the power intensity of the power supply back to the power supply with a predetermined threshold value; the control system (not shown) determines whether to stop the process or continue to compare based on the reflected power supply. A successful comparison means that a stable plasma is formed within 1 7 t of the plasma source. 9. Assuming that the decision is to continue, the vacuum wafer base 16 is commanded to begin rotating at a predetermined angular velocity. 10. Commanding the vacuum wafer susceptor 16 to move on the X, Y, and Z axes, thereby enabling

Page 12 1281199 Amendment Case No. 92109291 . V. INSTRUCTIONS (9) The edge surface enters the flow of reactive gas flowing out of the reactive gas channel 30 t. 1 1. The film formation is controlled by the movement dynamics of the vacuum wafer susceptor 16, as follows: 1. 2. Referring to Figures 3 and 5, the wafer 10 is smoothly accelerated. Moving from the starting position along the positive X direction; when the edge of the wafer 10 moves below the reactive gas channel 30 t, the ceria film fragments begin to react with the fluorine atoms in the reactive gas stream to produce an easy Volatile by-products based on the following chemical equation:

Si02

4F ->

SiF4 02 When the process effluent, Si F4 + 02 is generated, the exhaust space 23 directs the effluent stream to the exhaust system (not shown) controlled by the conductive control valve 24. The wafer 10 continues to move in the positive X-axis direction, causing the major portion of the film 11 to contact the reactive gas flowing through the channel 10 t, and the aforementioned chemical reaction will remove a portion of the film 11. When the pre-calculated edge exclusion limit is reached, the vacuum wafer base 16 is instructed to reverse the direction and move at a smooth deceleration until it returns to the original starting position. When applied to the film profiles 1 1 and 1 2 as shown in Fig. 2A, the aforementioned movement will produce a cerium oxide removal profile, thereby producing a film profile 11 as shown in Fig. 2B. 1. Once the film removal forming step is completed, the RF power supply is turned off. 1 4. Close the process input gas shutoff valve 2 7 t. 15. Close the dilution/cooling gas shutoff valves 26 t and 26 b. 16. Close the conductive control valve of the dilution/cooling gas supply channel

Page 13 1281199 _ Case No. 92109291_年月日日__ V. Description of invention (10) 21 Bu 1 7. Close the conductive control valve of the casing exhaust space. According to this application, some metal films may be exposed during the oxide removal step. To prevent spalling of these metal films, a film of ruthenium dioxide may be deposited first, as described below: 1 8. Reference 6 and 7 show the dilution/cooling gas flow rate setpoints to the mass flow control (MFCs) 25 1:" and 2 5bn and command the dilution/cooling gas shutoff valves 25tn and 2 5bn to open; The gas begins to flow and fills the dilution/cooling gas supply channels 1 9 tπ and 1 9 bπ and strikes the wafer 10 edge.

1. Command the elongated exhaust passage conductive control valve 2 11π to open to a predetermined position. (The conductive control valve 2 1 bπ is not opened, so that the dilution/cooling gas does not flow out from the channel 19bn to protect the back surface of the wafer 10 from unwanted reactive gases). 2 0, the process gas flow rate set value is transmitted to the process input gas mass flow controller (not shown), and the process input gas shut-off valve 2 7 t ” is turned on; the process input gas 氦 (He ), tetraoxygen B The base (TEOS) and ozone (03) begin to flow through the channel 3 0 t 丨, °

2 1. Command the outer casing exhaust space 2 3 of the conductive control valve 2 4 π to open to a predetermined position. 2 2. Transfer a power setting to the RF power supply 2 9 tπ and command the RF power to turn on. The plasma and reactive gas formed in the plasma source 1 7 tπ begins to flow through the channel 3 0 tπ into the outer casing exhaust space 2 3 and flows out of the conductive control valve 2 4 π to the exhaust system (Fig.

Page 14 1281199 Case No. 92109291

_5, not shown in the description of the invention (11). 23. The impedance matching network 28t" adjusts the load impedance to fit the output impedance of the power supply 2 9 tπ. The control system 3 compares the reflected voltage back to the power supply 2 9 t" in the power supply diagram. Threshold; control system (not shown), husband, and a process or continue to compare based on reflected power. A 疋 较 较 较 较 较 较 较 较 较 较 较 较 较 较 较 较 较 较 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电 电The predetermined angular velocity is rotated. Beginning with the command, the vacuum wafer pedestal moves its edge surface on the X, γ, and Z axes into the reactive gas flow from the reactive gas channel 3 〇 t", ☆ '. < The formation of the film deposition is controlled by the state of the vacuum wafer pedestal, as follows: The wafer 10 moves from the starting position in the X and γ axis directions, and the directional vector is directed to the plasma source 1 The direction of 7tn, and the way it finally moves steadily; when the edge of the wafer is moved by the flat gas channel 3 0 t, f, the yttria film starts, should be on a wafer 1 0 The surface is based on the following chemical equation: α 积 Si(OC2H5 ) + 803 -> Si02 +10H2O + "sc〇2 When the process effluent, 10H2O + 8C02 is generated, the exhaust space 23 guides the effluent stream to conduct electricity. Control the exhaust system controlled by the valve 24" (figure / not shown). The wafer 1 〇 continues to move to bring more etched film 丨丨 into contact with the reactive gas flow, and the aforementioned chemical reaction will continue to deposit the film 1 5. When it reaches the pre-calculated edge exclusion limit, the vacuum wafer base 24 25 26 27 is reversed to make it the most advanced.

Page 15 1281199 _ Case No. 92109291_年月日日__ V. Invention Description (12) 1 6 Reverse the direction and move it at a steady deceleration until it returns to the original starting position. When applied to the film profile 1 1 as shown in Fig. 2B, the aforementioned movement will produce a dioxin deposition profile, which in turn produces a film profile 15 as shown in Fig. 2C. 2 8. Once the film deposition forming step is completed, the RF power supply is commanded to be turned off. 2 9. Close the process input gas shut-off valve 2 7 tπ. 30. Close the dilution/cooling gas shut-off valve 26 t” 26bπ. 3 1. Close the conductive control valve of the dilution/cooling gas supply channel 2 11 ▼,.

3 2, close the conductive control valve of the housing exhaust space 2 4π. 3. After the continuous process is completed, the wafer 10 is removed from the vacuum wafer substrate 16. The etched surface profile can be any shape limited by the spatial frequency capability of the reactive gas travel state and the dynamic response of the servo system. Other related shapes may include a convex or concave shape or a shape that penetrates from the edge of the wafer to the top surface.

The protective film 15 can be of any suitable thickness. In general, the film 15 is sufficiently thin to prevent the film 15 from extending to the original film 1 1 plane, and it must also be thick enough to It has sufficient mechanical strength to withstand the stress generated by the film 11 covered with the protective film 15. For example, a thickness of from 0.1 to 3 micrometers (//m) should be sufficient, and the thickness of the film 15 can be varied with various etching process profiles by the residence time of the reactive gas. Space changes are determined. Therefore, the present invention provides an edge region of a semiconductor substrate in a process

Page 16 1281199 _ Case No. 92109291_年月日日__ V. Description of Invention (13) The apparatus and method for forming a film in a domain, and which are economical and relatively simple and efficient. The present invention also provides a method of easily removing debris from a semiconductor substrate and forming a predetermined shape at the edge of the substrate during the process. [Description of the number] 10 Wafer 11 Cover (film) 12 Debris 13 Photoresist layer 14 Particle 15 Film 16 Vacuum pedestal 17 Plasma source 18 Housing 19 Gas supply channel 20 Exhaust channel 21 Conductive control valve 22 Slot 23 Exhaust space 24 Conductive control valve 25 Mass flow controller 26 Gas shut-off valve 27 Gas shut-off valve 28 Impedance matching network 29 RF power supply 30 channels

Page 17 1281199 _ Case No. 92109291_Year of the Moon __ BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A is a partial cross-sectional view of a wafer having peeling film fragments in a peripheral edge region; FIG. 1B is a conventional technique at the first A schematic diagram of a photoresist layer on a wafer of A is used to solve the peeling film; FIG. 1C is a schematic view showing a photoresist layer of the wafer of FIG. 1B exposed by a conventional technique; FIG. 1D is a diagram A schematic diagram of the technique after completing the photoresist layer on the wafer of FIG. 1C. FIG. 1E is a schematic view of the prior art after wet or dry etching on the wafer of FIG. 1D.

FIG. 1F is a schematic view showing a conventional method of stripping a photoresist layer on a wafer of FIG. 1A and cleaning, and FIG. 2A is a partial cross-sectional view of a wafer having peeling film fragments in a peripheral edge region. 2B is a schematic view of the invention after removing the peeling film fragments on the wafer of FIG. 2A and forming the original film-bonding wheel gallery, and FIG. 2C is the surface of the wafer formed on the second B-picture of the present invention. 3 is a side view of the apparatus for etching a peripheral edge region of a wafer; FIG. 4 is a plan view of the apparatus of FIG. 3;

5 is an enlarged schematic view of a peripheral edge region of a wafer of the present invention during etching, and FIG. 6 is a side view of the device for depositing a thin film in a peripheral region of a wafer according to the present invention, and

Page 18 1281199 ^_Case No. 92109291_年月日日__ Schematic description of the drawing Figure 7 is an enlarged schematic view of the peripheral edge region of the wafer during film deposition. I··第19页

Claims (1)

1281199 _ Case No. 92109291 _^_ Stomach VI, Patent Application No. 1 · A device for forming a film on a wafer, comprising: a rotating base on which a wafer is held; and an outer casing having a narrow hole Receiving a wafer edge on the pedestal; at least one plasma source disposed on the outer casing to generate a reactive gas flow; a first passage located in the outer casing and the plasma source Cooperating, the reactive gas flows directly to the wafer located in the elongated hole of the outer casing; and the β-exhaust space is located in the outer casing to accommodate the reactive gas; An exhaust line connected and extending from the exhaust space to discharge the reactive gas of the exhaust space; at least one second passage located in the outer casing and radially in the first passage, Directing the dilution/cooling gas to the wafer; and at least one exhaust passage in the outer casing and between the second passage and the first passage to discharge the dilution/cooling gas and the reactive gas therefrom . 2. The device of claim 1, wherein the outer casing is semi-circular to receive a major portion of the wafer on the pedestal so as to be positioned within the elongated aperture. 3. The device of claim 1, wherein the exhaust passage is disposed between the plasma source and the first passage. 4) A device for forming a thin film on a wafer, comprising: " a rotating susceptor on which a wafer is held; Page 20, 1281199: _ case number 92109291 _ _ _ _ _ _ s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s The housing is configured to selectively generate and direct a flow of reactive gas to and radially exit the edge of the wafer within the elongated aperture of the housing; a plurality of channels are located within the housing to direct the dilution/cooling gas toward the reaction a direction of the gas flowing onto the wafer; and ~ a plurality of exhaust passages in the outer casing and between the passage and the plasma source to discharge the dilution/cooling gas and the reactive gas from the crucible 5. The device of claim 4, wherein the outer casing is semi-circular to receive a major portion of the wafer on the pedestal to be positioned within the elongated aperture. 6. The device of claim 4, wherein the plurality of plasma sources comprises three plasma sources respectively located around the outer casing to selectively etch the polymer on the wafer, The ruthenium dioxide on the wafer is etched and a layer of ruthenium dioxide is deposited on the wafer. 7 · The device described in claim 4, including an exhaust air The system is located in the outer casing for accommodating the reactive gas and an exhaust line which is connected and extended from the exhaust space to discharge the reactive gas in the exhaust space. 8 a method for forming a thin film on a wafer, comprising the steps of: disposing a wafer having a thin film on a rotating base; guiding a dilution/cooling gas to radially flow to the wafer; Page 21 1281199 _; _ case number 92109291 _ _ _ _ _ _ s s s s s s s s s s s s s s s s s s s s s s The wafer radially exits the dilution/cooling gas to react the reactive gas with the wafer; and rotates the wafer to remove the film fragments of the wafer edge by the flow of the reactive gas . u 9 · The method of claim 8 further includes rotating the crystal The wafer is moved in a circular direction and in a linear direction, and the material on the wafer film is removed by the flow of the reactive gas to form the film into a predetermined shape. The method of claim 9, further comprising directing the reactive gas to the wafer for a second time, and radially flowing the dilution/cooling gas to make the reactive gas and the wafer A reaction is formed to deposit a material thereon, and the wafer is rotated to deposit a protective film on the formed film of the wafer by the second flow of the reactive gas. I. Between 0. 3微米之间。 The thickness of the protective film is between 0.1 to 0.3 microns. 1 2 The method of claim 10, further comprising collecting a reactive gas in a space at an edge of the wafer and discharging the reactive gas from the space. 1 3 — A method of forming a thin film on a wafer, comprising the steps of: ” placing a wafer having a thin film on a rotating pedestal; Page 22 1281199 _, Case No. 92109291 _ _ _ _ _ _ _ _ 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 Diluting/cooling gas; directing a reactive gas to the wafer, and radially flowing the dilution/cooling gas to react the reactive gas with the wafer; and rotating the wafer to utilize reactive gas deposition A protective film of a material is on the edge of the wafer. 1 至0. 3微米之间。 The thickness of the protective film is between 0.1 to 0.3 microns. Page 23 1281199 Second _ Case No. 92109291_Year, Month 曰 _ Amendment u VI. Designation of representative map (1) The representative figure of this case is: Figure 3 (2), the representative symbol of the representative figure of this case is a simple description: Page 3 10 Wafer 16 Vacuum pedestal 17 Plasma source 18 Housing 19 Gas supply channel 20 Exhaust channel 21 Conductive control valve 22 Slothole 23 Exhaust space 24 Conductive control valve 25 Mass flow controller 26 Gas shut-off valve 27 Gas Shutoff valve 28 impedance matching network 29 RF power supply