KR100499172B1 - Method for measuring a tilted angle of a semiconductor substrate in an ion implantation process - Google Patents

Abstract

A method for measuring an inclination angle at which a semiconductor substrate is disposed in a process of implanting ions into a semiconductor substrate is disclosed. During the ion implantation process, the shadow jig blocks a portion of the ion beam irradiated onto the semiconductor substrate to form a shadow on the semiconductor substrate. Since the size of the shadow formed on the semiconductor substrate is changed according to the inclination angle at which the semiconductor substrate is disposed, the size of the shadow formed on the semiconductor substrate is measured, and the size of the shadow is measured by comparing the measured shadow size with a preset reference size. The angle of inclination can be measured.

Description

Method for measuring a tilted angle of a semiconductor substrate in an ion implantation process

The present invention relates to an ion implantation process of a substrate. More particularly, the present invention relates to a method for measuring a tilted angle at which a semiconductor substrate is disposed in an ion implantation process.

In general, a semiconductor device includes a Fab process for forming an electrical circuit on a silicon wafer used as a semiconductor substrate, a process for inspecting electrical characteristics of the semiconductor devices formed in the fab process, and the semiconductor devices are epoxy It is manufactured through a package assembly process for encapsulating and individualizing with resin.

The fab process includes a deposition process for forming a film on a semiconductor substrate, a chemical mechanical polishing process for planarizing the film, a photolithography process for forming a photoresist pattern on the film, and the photoresist pattern. An etching process for forming the film into a pattern having electrical characteristics, an ion implantation process for implanting specific ions into a predetermined region of the semiconductor substrate, a cleaning process for removing impurities on the semiconductor substrate, and the film or pattern Inspection process for inspecting the surface of the formed semiconductor substrate;

In the unit process, an ion implantation process is a process of forming a source and a drain of a transistor by implanting specific ions into a predetermined portion of a semiconductor substrate. The main technique in the ion implantation process is to implant the specific ions to a uniform depth to form the source and drain. The ion implantation process has an advantage that the implantation depth and the amount of ions implanted into the source and drain regions can be controlled over the thermal diffusion technique. As an example of an apparatus for performing the ion implantation process, US Pat. Nos. 5,343,047 (issued to Ono, et al.) And 5,641,969 (Cooke, et al.) Disclose ion implantation devices and ion implantation systems. .

In the ion implantation process, certain ions are implanted at a non-uniform depth by the channeling effect of the crystal structure of silicon constituting the semiconductor substrate. For this reason, the semiconductor substrate should be arranged to have a predetermined inclination angle with respect to the direction of the ion beam.

The ion beam is irradiated in a horizontal direction from the ion source, and the semiconductor substrate is arranged to have an inclination angle of about 7 ° with respect to the vertical line by a platen. In this case, a gate pattern of a transistor is formed on a surface of the semiconductor substrate, and a shadow effect is generated on one side of the transistor gate pattern by the inclination angle.

In order to compensate for the shadow effect, a method of implanting ions while rotating a semiconductor substrate has been proposed. For example, a method of compensating the shadow effect by first implanting ions into a semiconductor substrate, then rotating the semiconductor substrate by 180 ° and secondly implanting ions into the semiconductor substrate.

However, when the semiconductor substrate is not disposed at a predetermined inclination angle, the implantation depth of ions is changed, and the width of the shadow is changed. That is, when the inclination angle of the semiconductor substrate is less than or greater than 7 ° with respect to the vertical line due to the defect of the ion implantation device, the depth of the ions injected under the gate pattern of the semiconductor substrate and the width of the shadow formed by the gate pattern are changed. This causes problems such as deterioration of transistor characteristics and poor operation.

The width change of the shadow due to the inclination angle error of the semiconductor substrate is small and cannot be found in the subsequent inspection process. For example, when the height of the gate pattern of the transistor is 4500 kW, the width of the shadow is about 55 nm. At this time, since the spot size of the laser beam of the thermal wave (TW) measuring apparatus for measuring the amount of ions implanted in the semiconductor substrate is 1 μm or more, it is not easy to detect the shadow. In addition, the shadow may not be easily detected through image analysis using a scanning electron microscope (SEM) and component analysis through a particle analysis device. Therefore, when the semiconductor substrate is not disposed at a predetermined inclination angle due to a defect of the ion implantation device, it is almost impossible to detect this.

Since the above problem cannot be immediately confirmed after the ion implantation process, the semiconductor device is detected as defective in the process of inspecting the electrical characteristics of the semiconductor device after all the manufacturing processes of the semiconductor device are completed. This causes considerable time and material loss, and serves as a major cause of lowering the yield of the semiconductor substrate. In addition, since the manufacturing process of the semiconductor device is generally performed in run units, the damage caused by the tilt angle error of the semiconductor substrate in the ion implantation process is further increased.

An object of the present invention for solving the above problems is to provide a method that can easily measure the inclination angle of the semiconductor substrate disposed with respect to the traveling direction of the ion beam in the ion implantation process.

The present invention for achieving the above object, the step of interposing a shield for blocking a portion of the ion beam between the ion source for providing the ion beam and the substrate disposed to have an inclination angle with respect to the traveling direction of the ion beam, and the substrate Irradiating the ion beam toward to form a shadow by the shield on the substrate, measuring the size of the shadow by measuring the amount of ions injected into the substrate, and setting a predetermined reference size And a tilt angle of the substrate is measured by comparing the measured shadow size with the size of the measured shadow.

According to one embodiment of the invention, the shield is connected to the chuck for supporting the semiconductor substrate, and includes a shadow jig for blocking a portion of the ion beam. During the first ion implantation process, a first shadow is formed on the edge of the semiconductor substrate by the shadow jig. Subsequently, the semiconductor substrate is rotated at a preset rotation angle (eg, 180 °), and a secondary ion implantation process is performed. While the secondary ion implantation process is performed, a second shadow formed by the shadow jig is formed on the edge of the semiconductor substrate. The amount of ions implanted in the semiconductor substrate can be measured by the thermal wave value of the surface of the semiconductor substrate. The magnitudes of the first shadow and the second shadow are measured by the measured thermal wave values, and the inclination angle of the semiconductor substrate is calculated by comparing the measured sizes of the first shadow or the second shadow with a preset reference size. Here, the preset reference size is determined according to the inclination angle of the semiconductor substrate and the size of the shadow jig.

According to one embodiment of the present invention as described above, during the ion implantation process, it is easy to know whether the semiconductor substrate is disposed at a normal inclination angle, so that the defect of the ion implantation process due to the inclination angle error of the semiconductor substrate can be early It can be prevented. In addition, it is possible to prevent time and material loss due to the poor ion implantation process.

Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a flowchart illustrating a method of measuring a substrate tilt angle in an ion implantation process according to a preferred embodiment of the present invention.

Referring to FIG. 1, a method of measuring a substrate tilt angle in an ion implantation process according to the embodiment is as follows.

First, a shadow jig for blocking a portion of the ion beam is interposed between an ion source for providing an ion beam and a semiconductor substrate arranged at a predetermined inclination angle (S100). The semiconductor substrate is supported at a predetermined inclination angle by the chuck. The chuck includes a platen for adsorbing a semiconductor substrate using electrostatic force and a support member for supporting the platen. The platen has a disk shape, and an accommodating groove for accommodating the platen is formed at one side of the support member. In this case, the shadow jig is located at one side of the semiconductor substrate. That is, the semiconductor substrate is located behind the shadow jig so that the shadow jig blocks a portion of the ion beam provided from the ion source.

The shadow jig is installed to be movable on the support member, and the drive unit moves the shadow jig. The shadow jig is moved outwardly of the chuck by the drive unit during loading and unloading of the semiconductor substrate, and is moved in the direction of the center of the chuck by the drive unit during the ion implantation process of the semiconductor substrate and positioned above the edge of the semiconductor substrate. do.

Subsequently, the first shadow is formed on the semiconductor substrate by irradiating the ion beam toward the semiconductor substrate (S120). At this time, the first shadow is formed at the edge of the upper surface of the semiconductor substrate and cannot be observed with the naked eye. That is, part of the ion beam supplied to the semiconductor substrate is blocked by the shadow jig, and the rest is injected into the semiconductor substrate. The first shadow refers to a region where ions are not implanted. When electrical patterns are formed on the semiconductor substrate, it is preferable that the first shadow does not invade the region where the electrical patterns are formed. Most preferably, it is formed in the edge exposure of wafer (EEW) of the substrate. Here, the edge exposure region means an edge region of a semiconductor substrate from which a photoresist film is removed in a photolithography process for forming an electrical pattern on the semiconductor substrate.

The traveling direction of the ion beam is a horizontal direction, where the semiconductor substrate has a predetermined inclination angle with respect to the traveling direction of the ion beam. At this time, the inclination angle of the preset semiconductor substrate is about 7 ° with respect to the vertical line, and the incident angle of the ion beam is about 83 °. However, it cannot be visually confirmed whether the semiconductor substrate actually has an inclination angle of 7 ° with respect to the vertical line.

On the other hand, when the cross-sectional shape of the ion beam is considerably smaller than the area of the semiconductor substrate, the ion beam scans the semiconductor substrate in the horizontal direction by the ion deflection meter, and the semiconductor substrate moves in the vertical direction according to the scanning of the ion beam. When the cross-sectional shape of the ion beam is a ribbon shape in the horizontal direction, the ribbon ion beam scans the semiconductor substrate by moving the semiconductor substrate in the vertical direction. In contrast, it is also possible for a ribbon ion beam to scan the semiconductor substrate in a vertical direction by means of an ion deflectometer. In addition, various scanning methods may be used.

Subsequently, the semiconductor substrate on which the first shadow is formed is rotated at a predetermined rotational angle (for example, 180 °). (S130) At this time, the rotation angle of the semiconductor substrate is appropriate according to the shape of the pattern formed on the surface of the semiconductor substrate. Can be adjusted.

Next, a second shadow is formed on the semiconductor substrate by irradiating an ion beam toward the semiconductor substrate. (S140) The second shadow is formed on the opposite side of the first shadow with respect to the center of the semiconductor substrate, and cannot be visually observed. .

Subsequently, the amount of ions implanted into the semiconductor substrate is measured to measure the size of the first shadow formed in the first ion implantation process and the second shadow formed in the second ion implantation process (S150). According to the bar, since the shadow jig is disposed on one side of the support member, the widths of the first shadow and the second shadow are changed according to the inclination angle of the semiconductor substrate. However, the shadow jig may be located above the support member, in which case the lengths of the first shadow and the second shadow are changed according to the inclination angle of the semiconductor substrate.

The amount of ions implanted in the semiconductor substrate can be detected through various methods. For example, image analysis using a scanning electron microscope, measurement of thermal wave values on a surface of a semiconductor substrate, energy analysis through surface resistance of a semiconductor substrate, and the like. Preferably, the size of the first shadow and the second shadow may be measured by measuring the thermal wave surface value of the semiconductor substrate.

Here, the thermal wave value indicates a degree of damage of the wafer surface caused by ion implantation. The thermal wave value increases as the degree of damage increases. That is, as the implantation energy of ions increases, the amount of implanted ions increases, and as the atom mass unit (AMU) of the implanted ions increases, the thermal wave value increases. The thermal wave value is measured by a thermal probe device, the thermal probe device irradiates a laser beam on the surface of the semiconductor substrate implanted with ions, detects a laser beam reflected from the surface of the semiconductor substrate, The thermal wave value is measured according to the reflectivity of the substrate surface.

Next, the inclination angle of the semiconductor substrate is calculated by comparing the measured size of the first shadow or the second shadow with the preset reference size (S160). That is, when the preset reference size is exactly 7 ° the inclination angle of the semiconductor substrate is calculated. In the case of the shadow size, the inclination angle of the semiconductor substrate may be relatively calculated by comparing the measured shadow size with a reference size.

The method for measuring the tilt angle of a semiconductor substrate in the ion implantation process according to the embodiment may be applied to a semiconductor substrate on which a pattern is formed, and may also be applied to a bare wafer. In the ion implantation process performed on a run basis, the inclination angle measurement process may be performed on the first semiconductor substrate to inspect the operating state of the ion implantation apparatus, thereby performing stable ion implantation on subsequent semiconductor substrates. In addition, by performing an inclination angle measurement process on the bare wafer before performing the ion implantation process in each run unit, a stable ion implantation process may be performed on all the semiconductor substrates belonging to the run. That is, the reliability of the ion implantation process can be improved by confirming in advance whether the semiconductor substrate is exactly disposed at a predetermined inclination angle with respect to the traveling direction of the ion beam. In addition, when the semiconductor substrate is not disposed at a predetermined inclination angle, the ion implantation process may be stably performed by correcting the semiconductor substrate.

FIG. 2 is a schematic diagram illustrating an ion implantation apparatus for performing a method of measuring a substrate tilt angle in the ion implantation process illustrated in FIG. 1.

Referring to FIG. 2, the ion implantation apparatus 100 includes an ion source 102 for providing an ion beam made of ions, and an ion implantation chamber 104 for performing an ion implantation process. The chuck 110 for handling the semiconductor substrate 10 is disposed inside the ion implantation chamber 104, and the chuck 110 has a platen 112 for adsorbing the semiconductor substrate 10 using electrostatic force. , A support member 114 for supporting the platen 112.

The platen 112 has a disk shape, and a receiving groove for accommodating the platen 112 is formed in the first surface of the support member 114. The second surface of the support member 114 is connected to the platen 112 through the support member 114 and the first driving unit 116 for rotating the platen 112 is connected.

In addition, a second driving unit 118 for adjusting the inclination angle of the semiconductor substrate 10 is connected to the second surface of the support member 114. The second driving unit 118 is disposed on the base plate 120, and the driving shaft 122 and the third driving unit 124 are provided on the lower surface of the base plate 120 to move the chuck 110 in the vertical direction. ) Is connected.

A motor may be used as the first driving unit 116 and the second driving unit 118, and a step motor capable of adjusting the rotation angle is preferable. The third drive unit 124 includes a motor 124a and a ball screw 124b and a ball nut 124c for providing rotational force. The configuration of the first, second and third driving units 116, 118, 124 may be variously changed.

The semiconductor substrate 10 is loaded into the chuck 110 in a horizontal state and unloaded from the chuck 110. On the other hand, during the ion implantation process, the semiconductor substrate 10 is disposed at a predetermined inclination angle by the second driving unit 118. The first driving unit 116 rotates the semiconductor substrate 10 having a predetermined inclination angle to adjust the incident angle of the ion beam incident on the semiconductor substrate 10. In this case, the traveling direction of the ion beam is a horizontal direction, and the inclination angle of the preset semiconductor substrate is about 7 ° with respect to the vertical line.

Meanwhile, a shadow jig 130 for blocking a portion of the ion beam supplied from the ion source 102 is connected to one side of the chuck 110. The shadow jig 130 is connected to the edge of the first surface of the support member 114 and forms a shadow on the edge portion of the semiconductor substrate 10 adsorbed to the platen 112 during the ion implantation process.

The shadow jig 130 cuts off a portion of the ion beam supplied to the semiconductor substrate 10 to form shadows at the edges of the semiconductor substrate 10 and the edges of the support member 114. It is connected to and includes an installation bracket (134, bracket) for installing the shadow bar 132 to the support member 114. The shadow bar 132 extends from the mounting bracket 134 toward the center of the semiconductor substrate 10 and does not exceed the edge exposure area of the semiconductor substrate 10. Here, the shadow bar 132 and the mounting bracket 134 should be made of a material having a high heat resistance, preferably made of a fluororesin. For example, a commercially available Teflon (registered trademark of Teflon, E.I. Dupont de Nemours & Co., and its generic name is PTFE (Polytetrafluoroethylene)) resin corresponds to fluorine resin.

The ion source 102 determines the polarity of the ion beam provided from the ion generator 140 that generates ions from the source gas, the ion extractor 142 that extracts the ion beam from the ion generator 140, and the ion extractor 142. A polarity converter 144 for converting to negative, a mass analyzer 146 for selecting specific ions from the negative ion beam, an accelerator 148 for accelerating and converting the polarity of the ion beam, and a focusing magnet (not shown) for adjusting the focus of the ion beam And an ion deflector 150 for adjusting the traveling direction of the ion beam, an ion current measuring unit (not shown) for measuring the ion current of the ion beam, and the like.

The ion generator 140 is an arc discharge type including an arc chamber, a filament, and the like, and generates ions using a collision between hot electrons provided from the filament and the source gas. In addition, ion generators such as a radio frequency type duoplasmatron, a cold cathode type, a sputter type, a penning ionization type, or the like may be used.

The polarity converter 144 includes a solid magnesium and a heater used as an electron donating material. A high heat of about 450 ° C. is provided to the solid magnesium from the heater, and gaseous magnesium molecules are released from the solid magnesium to collide with the extracted ion beam. By the collision of the magnesium molecule with the ion beam, the ion beam obtains electrons from the magnesium molecule and is converted into an ion beam having negative properties.

As described above, the ion beam having negative properties is provided to the accelerator by selecting only specific ions in the mass spectrometer 146.

Although not shown in detail, the accelerator 148 includes a first accelerator and a second accelerator. A stripper is provided between the first accelerator and the second accelerator to convert the negative ion beam into a positive ion beam. That is, the negative ion beam accelerated by the first acceleration unit is converted into a positive ion beam by the stripper and accelerated again by the second acceleration unit. A high voltage of several thousand to several mega volts is applied to the stripper, and nitrogen or argon gas may be used as the stripping gas to change the polarity.

The positive ion beam accelerated through the accelerator 148 is focused through the focusing magnet, and the traveling direction is adjusted by the ion deflector 150 to be provided to the semiconductor substrate 10. In this case, the ion deflector 150 adjusts the traveling direction of the ion beam so that the ion beam scans the semiconductor substrate 10.

When converted to a positive ion beam by a stripper, the positive ion beam contains ions having various energy levels. The ion source further includes an ion filter (not shown) for selecting ions having a specific energy from among ions having various energy levels included in the positive ion beam.

Although not shown, the ion current measuring unit is disposed between the mass spectrometer and the accelerator to measure the ion current of the negative ion beam and between the accelerator and the ion implantation chamber to measure the ion current of the positive ion beam. For a second Faraday system.

On the other hand, when the position of the shadow jig 130 is fixed, since the loading and unloading of the semiconductor substrate 10 is not easy, the agent for moving the shadow jig 130 during loading and unloading of the semiconductor substrate 10 Four drive units are required.

FIG. 3 is a schematic diagram illustrating a fourth driving unit for moving the shadow jig illustrated in FIG. 2, and FIG. 4 is a schematic plan view illustrating the fourth driving unit illustrated in FIG. 3.

3 and 4, the fourth driving unit 160 may include a rack gear 162 mounted to the support member 114 so as to be movable, a motor 164 and a rack gear 162 for providing driving force. And a pinion gear 166 for connecting the motor 164. The mounting bracket 134 of the shadow jig 130 is installed on the top surface of the rack gear 162, and the shadow bar 132 extends from the mounting bracket 134 toward the center of the platen 112. Guide grooves for guiding the movement of the rack gear 162 are formed in the upper surface of the support member 114, the rack gear 162 is coupled to the pinion gear 166 by the rotation of the pinion gear 166 Reciprocating inside the guide groove.

When the semiconductor substrate 10 is loaded onto the platen 112, the fourth driving unit 160 chucks the shadow jig 130 to prevent the semiconductor substrate 10 and the shadow jig 130 from interfering. Move to the side of (110). Subsequently, when the semiconductor substrate 10 is completely loaded on the platen 112, the fourth driving unit 160 moves the shadow jig 130 toward the center of the chuck 110. In this case, an end portion of the shadow bar 132 should not exceed the edge exposure area of the semiconductor substrate 10.

FIG. 5 is a schematic configuration diagram illustrating another example of the fourth driving unit illustrated in FIG. 3, and FIG. 6 is a schematic plan view illustrating another example of the fourth driving unit illustrated in FIG. 3.

5 and 6, the fourth driving unit 160 ′ includes a motor for rotating the shadow jig 130 ′. The fourth driving unit 160 ′ is disposed at the edge of the upper surface of the support member 114 and connected to the mounting bracket 134 ′ of the shadow jig 130 ′, and the shadow bar 132 ′ is mounted to the mounting bracket 134. ') Extends from the platen 112 in the center direction.

As shown, when the semiconductor substrate 10 is loaded onto the platen 112, the fourth driving unit 160 ′ may prevent the semiconductor substrate 10 from interfering with the shadow jig 130 ′. The shadow jig 130 'is rotated in the vertical direction. Subsequently, when the semiconductor substrate 10 is completely loaded on the platen 112, the fourth driving unit 160 ′ rotates the shadow jig 130 ′ in the horizontal direction. At this time, an end portion of the shadow bar 132 ′ should not exceed the edge exposure area of the semiconductor substrate 10.

FIG. 7 is a schematic diagram illustrating a step of forming a first shadow on a semiconductor substrate, and FIG. 8 is a schematic diagram illustrating a step of forming a second shadow on a semiconductor substrate. 9 is a plan view illustrating a semiconductor substrate on which first and second shadows are formed.

A shadow jig 130 having a width of 10 mm and a height of 10 mm is applied to the ion implantation apparatus 100, and when the inclination angle of the semiconductor substrate 100 is about 7 ° with respect to the vertical line, the shadow jig 130 is formed on the semiconductor substrate 10. The width of the shadow is 54 mm. In other words, the reference width of the shadow is 54mm.

As illustrated, while forming the first shadow S1, the rotation angle of the semiconductor substrate 10 adsorbed to the chuck 110 is 45 ° with respect to the vertical line, and while the second shadow S2 is formed, The rotation angle of the semiconductor substrate 10 is 225 degrees. In this case, the reference is a flat zone region of the semiconductor substrate 10.

However, under the above conditions, the widths of the first shadow S1 and the second shadow S2 measured when the inclination angle of the semiconductor substrate 10 is 5 ° and 6 ° with respect to the vertical line are 52.9 mm and 53.4, respectively. mm. In addition, when the semiconductor substrate 10 has an inclination angle of 8 ° and 9 ° with respect to the vertical line, respectively, the widths of the first shadow S1 and the second shadow S2 measured are 54.5 mm and 55.0 mm, respectively. Accordingly, by comparing the reference width of the shadow with the measured width of the first shadow S1 or the second shadow S2, it may be determined whether the semiconductor substrate 10 is disposed at a predetermined inclination angle, and the calculated semiconductor substrate ( A stable ion implantation process can be performed by correcting the inclination angle of the semiconductor substrate 10 based on the inclination angle of 10).

According to the present invention as described above, the shadow jig blocks a portion of the ion beam supplied to the semiconductor substrate to form a shadow on the semiconductor substrate. The inclination angle at which the semiconductor substrate is disposed during the ion implantation process is calculated by comparing the shadow size with the measured shadow size.

Therefore, the defect of an ion implantation process can be detected early, and the defect of an ion implantation process can be prevented in advance by correcting the inclination angle of a semiconductor substrate based on the calculated inclination angle of the semiconductor substrate. In addition, it is possible to prevent the time and material loss due to the poor ion implantation process, it is possible to improve the reliability and productivity of the semiconductor device.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

1 is a flowchart illustrating a method of measuring a substrate tilt angle in an ion implantation process according to a preferred embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating an ion implantation apparatus for performing a method of measuring a substrate tilt angle in the ion implantation process illustrated in FIG. 1.

FIG. 3 is a schematic diagram illustrating a fourth driving unit for moving the shadow jig illustrated in FIG. 2.

FIG. 4 is a schematic plan view for describing the fourth driving unit shown in FIG. 3.

FIG. 5 is a schematic configuration diagram illustrating another example of the fourth driving unit illustrated in FIG. 3.

FIG. 6 is a schematic plan view for describing another example of the fourth driving unit illustrated in FIG. 3.

7 is a schematic diagram illustrating a step of forming a first shadow on a semiconductor substrate.

8 is a schematic diagram illustrating a step of forming a second shadow on a semiconductor substrate.

9 is a plan view illustrating a semiconductor substrate on which first and second shadows are formed.

Explanation of symbols on main parts of drawing

10 semiconductor substrate 100 ion implantation apparatus

102 ion source 104 ion implantation chamber

110: Chuck 112: Platen

114: support member 116: first drive unit

118: second drive unit 120: base plate

122: drive shaft 124: third drive unit

130: shadow jig 132: shadow bar

134: mounting bracket 140: ion generator

142 Ion Extractor 144 Polarity Converter

146: mass spectrometer 148: accelerator

150: ion deflection meter 160: fourth drive unit

S1: first shadow S2: second shadow

Claims (6)

Interposing a shield for blocking a portion of the ion beam between an ion source for providing an ion beam and a substrate arranged to have an inclination angle with respect to the direction of travel of the ion beam; Irradiating the ion beam toward the substrate to form a shadow by the shield on the substrate; Measuring the size of the shadow by measuring the amount of ions implanted into the substrate; And And measuring a tilt angle of the substrate by comparing a preset reference size with a measured shadow size. The method of claim 1, wherein the amount of ions implanted into the substrate is measured by a thermal wave value of the surface of the substrate. The method of claim 1, wherein in the forming of the shadow, the ion beam scans the substrate in a horizontal direction, and the substrate moves up and down according to scanning of the ion beam. . The ion beam of claim 1, wherein in the forming of the shadow, the ion beam has a ribbon-shaped cross section and is provided in a horizontal direction, and the substrate moves up and down to scan the surface of the substrate. Substrate tilt angle measurement method of the implantation process. The method of claim 1, wherein the forming of the shadow comprises: Irradiating the ion beam toward the substrate to form a first shadow on the substrate by the shield; Rotating the substrate; And Irradiating the ion beam toward the substrate to form a second shadow by the shield on the substrate. The method of claim 1, wherein in the forming of the shadow, the shadow is formed at an edge portion of the substrate.