JP2006066686A - Method and apparatus for introducing impurities - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize an economical method and apparatus for introducing impurities with which a quantity of the impurities to be introduced can be precisely controlled and the impurities can be prevented from diffusing deeply. <P>SOLUTION: An amorphous processing chamber consists of a container 1, a specimen table 2 provided in the container 1, a window 3 provided oppositely to the table 2, and five Xe lamps 4 as an ultraviolet light source opposite to the table 2 across the window 3. A silicon substrate 5 as a specimen is mounted on the specimen table 2, and ultraviolet rays emitted from the Xe lamps 4 are radiated to the surface of the silicon substrate 5, thereby destroying a crystalline structure in the vicinity of the surface of the substrate 5 to be amorphized. Thereafter, by subjecting the amorphized substrate surface to ion supply treatment and activation treatment, extremely shallow impurities can be introduced onto the substrate surface. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an impurity introduction method and an impurity introduction apparatus, and more particularly to an impurity introduction method for introducing impurities into the surface of a solid sample such as a semiconductor substrate.

As a technique for introducing impurities into the surface of a solid sample, a plasma doping method is known in which impurities are ionized and introduced into a solid with low energy (see, for example, Patent Document 1). FIG. 10 shows a schematic configuration of a plasma processing apparatus used in a plasma doping method as a conventional impurity introduction method described in Patent Document 1. In FIG. 10, a sample electrode 43 for placing a sample 42 made of a silicon substrate is provided in a vacuum container 41. A gas supply device 44 for supplying a doping source gas containing a desired element, for example, B ₂ H _6, into the vacuum vessel 41 and a pump 45 for reducing the pressure inside the vacuum vessel 41 are provided. Can be kept at a pressure of. Microwaves are radiated from the microwave waveguide 46 into the vacuum vessel 41 through a quartz plate 47 as a dielectric window. A magnetic field microwave plasma (electron cyclotron resonance plasma) 49 is formed in the vacuum vessel 41 by the interaction between the microwave and a DC magnetic field formed from the electromagnet 48. A high frequency power source 51 is connected to the sample electrode 43 via a capacitor 50 so that the potential of the sample electrode 43 can be controlled. The gas supplied from the gas supply device 44 is introduced into the vacuum container 41 from the gas introduction port 52 and is exhausted from the exhaust port 53 to the pump 45.

In the plasma processing apparatus having such a configuration, the doping source gas introduced from the gas inlet 52, for example, B ₂ H _6, is converted into plasma by the plasma generating means including the microwave waveguide 46 and the electromagnet 48, and the plasma 49 Of boron ions is supplied to the surface of the sample 42 by the high frequency power source 51.

By the way, in general, a gas containing impurities that become electrically active when supplied to a sample such as a silicon substrate, such as a doping source gas made of B ₂ H ₆ , is harmful to humans or has high reactivity. There is a problem that the risk is high.

In the plasma doping method, all of the substances contained in the doping source gas are introduced into the sample. Taking a doping source gas made of B ₂ H ₆ as an example, boron is the only effective impurity when introduced into the sample, but hydrogen is also introduced into the sample at the same time. When hydrogen is introduced into the sample, there is a problem that lattice defects occur in the sample during subsequent heat treatment such as epitaxial growth.

  Therefore, an impurity solid containing impurities that become electrically active when introduced into the sample is placed in a vacuum vessel, and plasma of a rare gas is generated in the vacuum vessel, and the impurity solid is sputtered by ions of the inert gas. Thus, a method has been proposed in which impurities are separated from impurity solids and the separated impurities are supplied to a sample (see, for example, Patent Document 2). FIG. 11 shows a schematic configuration of a plasma doping apparatus used in a plasma doping method as a conventional impurity introduction method described in Patent Document 2. In FIG. 11, a sample electrode 43 for placing a sample 42 made of a silicon substrate is provided in a vacuum vessel 41. A gas supply device 44 for supplying an inert gas into the vacuum vessel 41 and a pump 45 for reducing the pressure inside the vacuum vessel 41 are provided, and the inside of the vacuum vessel 41 can be maintained at a predetermined pressure. Then, microwaves are radiated from the microwave waveguide 46 into the vacuum vessel 41 through a quartz plate 47 as a dielectric window. A magnetic field microwave plasma (electron cyclotron resonance plasma) 49 is formed in the vacuum vessel 41 by the interaction between the microwave and the direct-current magnetic field formed from the electromagnet 48. A high frequency power source 51 is connected to the sample electrode 43 via a capacitor 50 so that the potential of the sample electrode 43 can be controlled. An impurity solid 54 containing an impurity element such as boron is provided on a solid holding table 55, and the potential of the solid holding table 55 is controlled by a high-frequency power source 57 connected via a capacitor 56. The gas supplied from the gas supply device 44 is introduced into the vacuum container 41 from the gas introduction port 52 and is exhausted from the exhaust port 53 to the pump 45.

  In the plasma doping apparatus having such a configuration, an inert gas, for example, argon (Ar) introduced from the gas introduction port 11 is converted into plasma by the plasma generating means including the microwave waveguide 46 and the electromagnet 48, and the impurity solid 54. Then, a part of the impurity element jumping out into the plasma by sputtering is ionized and introduced into the surface of the sample 42.

  Usually, a gate oxide film made of a thermal oxide film or the like is formed on the surface of the sample 42, and a conductive layer to be a gate electrode is formed thereon by a CVD method or the like, and this is patterned to form a gate electrode pattern. . The sample 42 in which the gate electrode is formed in this way is set in a plasma doping apparatus, and impurities are introduced in a self-aligning manner using the gate electrode as a mask by the above-described method, thereby forming a source / drain region, thereby forming a MOS transistor. Is obtained. However, it is necessary to perform an activation process because a transistor cannot be formed only by introducing impurities by plasma doping process. The activation process is a process in which a layer into which an impurity is introduced is heated using a method such as laser annealing or flash lamp annealing to make it active in a crystal. At this time, the shallow activation layer can be obtained by effectively heating the very thin layer into which the impurity is introduced. In order to effectively heat an extremely thin layer into which an impurity has been introduced, before the impurity is introduced, the absorption rate of light irradiated from a light source such as a laser or a lamp is increased in the extremely thin layer into which the impurity is to be introduced. Processing to be performed is performed. This process is called pre-amorphization. In the plasma processing apparatus having the same configuration as the plasma processing apparatus described above, plasma such as He gas is generated, and ions such as He generated are directed to the substrate by a bias voltage. It is accelerated and collided to destroy the crystal structure on the surface of the substrate to make it amorphous, and has already been proposed by the present inventors (for example, see Non-Patent Document 1).

US Pat. No. 4,912,065 JP 09-1115851 A Y. Sasaki et al. "B2H6 Plasma Doping with In-situ He Pre-amorphization", 2004 Symposia on VLSI Technology and Circuits.

However, the above method has a problem that it is not economical because an expensive vacuum processing apparatus for exclusive use is required to make the material amorphous. It is not impossible to use both a vacuum processing apparatus for performing plasma doping and a vacuum processing apparatus for amorphizing, but when repeatedly used, deposits such as boron adhering to the inner wall of the vacuum vessel are amorphous. Since it is introduced into the substrate surface even during the qualitative process, there is a problem that it is difficult to precisely control the amount of impurities introduced as a whole. In addition, since the amorphous part and the crystal part form a relatively clear boundary, the deep part of the amorphous part (near the boundary with the crystal part) is excessively heated during the activation process. There is a problem that the impurities diffuse deeply.
In view of the above-described conventional problems, an object of the present invention is to provide an impurity introduction method and apparatus that is economical, can accurately control the amount of impurity introduction, and can form a shallow impurity region.

Therefore, the impurity introduction method of the present invention includes a step of irradiating the sample with ultraviolet light, a step of supplying impurity ions to the surface of the sample, and a step of heating and activating the surface layer of the sample. .
With this configuration, the process of amorphizing the substrate surface by ultraviolet irradiation and the process of supplying impurity ions to the surface of the sample can be carried out separately, making it possible to perform economical processing and introducing impurities. The amount can be controlled precisely. In addition, since the portion made amorphous by the amorphization treatment by ultraviolet irradiation and the crystal portion form a relatively unclear boundary, a deep portion of the amorphous portion (crystal It is possible to prevent the impurities from being diffused deeply without excessively heating the vicinity of the boundary with the portion.

Moreover, the impurity introduction | transduction method of this invention contains what the wavelength of the ultraviolet-ray in the process of irradiating a sample with an ultraviolet-ray is 100 to 380 nm.
With this configuration, an efficient amorphization process can be performed.

Furthermore, the impurity introduction method of the present invention includes a method in which the wavelength of ultraviolet rays is 147 nm or more and 380 nm or less in the step of irradiating the sample with ultraviolet rays.
With this configuration, an inexpensive light source and an inexpensive window material can be used, and the amorphization process can be performed extremely economically.

Furthermore, in the impurity introduction method of the present invention, the step of supplying the impurity ions is performed by supplying high-frequency power to a plasma source while supplying a gas containing an impurity element, generating plasma, and generating impurities on the surface of the sample. Includes a process for supplying ions.
In addition, the step of supplying impurity ions to the surface of the sample places the sample on the sample electrode in the vacuum vessel, and evacuates the vacuum vessel while supplying the gas containing the impurity element into the vacuum vessel from the gas supply device. In addition, while controlling the inside of the vacuum vessel to a predetermined pressure, plasma is generated in the vacuum vessel by supplying high frequency power to the plasma source, and by supplying voltage to the sample electrode, impurity ions are generated on the surface of the sample. It is desirable to supply.
With this configuration, a shallow junction can be easily obtained.

Furthermore, in the impurity introduction method of the present invention, the step of activating includes a step of irradiating a laser beam.
With this configuration, since the laser light hardly changes over time, stable activation is possible.

Furthermore, in the impurity introduction method of the present invention, the step of activating includes a step of irradiating the flash lamp.
With this configuration, since the flash lamp is inexpensive, the cost can be reduced.

The impurity introduction apparatus of the present invention comprises an ultraviolet light source, irradiates the sample with ultraviolet light, and comprises an amorphization treatment chamber for amorphizing the surface of the sample, a plasma source, and impurity ions on the surface of the sample And an activation light treatment chamber that includes an annealing light source and heats and activates the surface layer of the sample by the annealing light source.
With this configuration, the amorphization process chamber for amorphizing the substrate surface by ultraviolet irradiation and the impurity supply process chamber for supplying impurity ions to the surface of the sample are configured separately. Unlike the case where the crystallization process and the impurity supply process are performed, the amorphization process is not performed in a state of being contaminated by impurities attached to the apparatus, and the impurity introduction amount can be precisely controlled. In addition, processing can be performed in parallel, and high-speed and economical processing is possible. Furthermore, since it has become amorphous due to ultraviolet irradiation, the amorphous part and the crystalline part form a relatively unclear boundary. It is possible to suppress deep diffusion of impurities without excessively heating the vicinity of the boundary with the crystal portion.

  This impurity introducing device is, for example, an impurity introducing device having at least three processing chambers, an amorphization processing chamber having a sample stage and an ultraviolet light source, a vacuum vessel, a sample electrode, and a vacuum vessel. A gas supply device for supplying gas to a gas, an exhaust device for exhausting the inside of the vacuum vessel, a pressure control device for controlling the pressure in the vacuum vessel, a plasma source, a high frequency power source for supplying high frequency power to the plasma source, An ion supply processing chamber provided with a voltage source for supplying a voltage to the electrode, and an annealing processing chamber provided with a sample stage and a light source for annealing are provided.

  Moreover, the impurity introduction apparatus of the present invention includes one in which the annealing light source is a laser light source.

  Moreover, the impurity introduction apparatus of the present invention includes an apparatus in which the annealing light source is a flash lamp light source.

Moreover, the impurity introduction | transduction apparatus of this invention contains what the wavelength of the said ultraviolet-ray is 100 to 380 nm.
With this configuration, an efficient amorphization process can be performed.

Moreover, the impurity introduction | transduction apparatus of this invention contains the thing whose wavelength of the said ultraviolet-ray is 147 nm or more and 380 nm or less.
With this configuration, an inexpensive light source and an inexpensive window material can be used, and the amorphization process can be performed extremely economically.
Preferably, the ultraviolet light source is an Xe lamp. Alternatively, the ultraviolet light source may be an ArF laser, or the ultraviolet light source may be a KrF laser.
With such a configuration, an inexpensive light source and an inexpensive window material can be used, and an amorphization process can be performed extremely economically.

  As described above, according to the impurity introduction method and apparatus of the present invention, it is economical, the impurity introduction amount can be precisely controlled, the impurity is prevented from being deeply diffused, and the shallow impurity region is formed. A possible impurity introduction method and apparatus can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
Hereinafter, Embodiment 1 of the present invention will be described in detail with reference to FIGS. 1 to 7.
The present embodiment is characterized in that, by irradiating ultraviolet rays prior to the introduction of the impurities, the region to which the impurities are to be introduced is made amorphous, and then the impurity is supplied to perform the activation treatment. Therefore, the amorphization process, the impurity supply process, and the activation process are performed in separate processing apparatuses, and here, the amorphization process will be described first.

  FIG. 3 shows a cross-sectional view of the amorphization treatment chamber in the impurity introduction apparatus used in Embodiment 1 of the present invention. As shown in FIG. 1, this amorphization processing chamber sandwiches a container 1, a sample table 2 provided in the container 1, a window 3 provided facing the sample table 2, and the window 3. And five Xe lamps 4 as ultraviolet light sources opposed to the sample stage 2.

  First, at the time of amorphization, as shown in FIG. 1, a silicon substrate 5 on which a gate insulating film and a gate electrode (not shown) are formed is placed on a sample stage 2 as a sample, and an Xe lamp 4 When the surface of the silicon substrate 5 is irradiated with ultraviolet rays emitted from the silicon substrate 5, the crystal structure near the surface of the silicon substrate 5 is destroyed and becomes amorphous. Typical processing conditions are Xe lamp driving power: 20 W × 5, total luminous flux: 1200 lumens, irradiation time: 110 seconds.

At this time, in order to suppress a chemical reaction such as an oxidation reaction on the surface of the silicon substrate, it is desirable to fill the container 1 with an inert gas such as He, Ar, N ₂ or the like. In this case, a gas introduction device (not shown) for introducing gas to the container 1 is connected in advance. The container 1 may be configured as a vacuum container and irradiated with ultraviolet rays in a vacuum state. In this case, a chemical reaction on the substrate surface can be more effectively suppressed.

  Next, the ion supply process will be described. FIG. 2 shows a cross-sectional view of the ion supply processing chamber in the impurity introduction apparatus used here. As shown in FIG. 2, the ion supply processing chamber includes a vacuum vessel 6, a turbo molecular pump 8 as an exhaust device that exhausts the inside of the vacuum vessel 6, and a pressure control device that controls the pressure in the vacuum vessel 6. A pressure regulating valve 9, a coil 13 as a plasma source provided in the vicinity of the dielectric window 12 facing the sample electrode 11, a high-frequency power source 10 for supplying high-frequency power of 13.56 MHz to the coil 13, and a sample electrode 11 It is comprised with the high frequency power supply 14 as a voltage source which supplies a voltage.

  While a predetermined gas is introduced from the gas supply device 7 into the vacuum container 6 of the ion supply processing chamber, the turbo molecular pump 8 as an exhaust device is evacuated, and the pressure regulating valve 9 as a pressure control device 9 Is maintained at a predetermined pressure. Then, the high frequency power supply 10 supplies high frequency power of 13.56 MHz to the coil 13 as a plasma source, thereby generating inductively coupled plasma in the vacuum vessel 6. In this state, a silicon substrate 5 (one subjected to an amorphization process) as a sample is placed on the sample electrode 11. Further, high frequency power is supplied to the sample electrode 11 by a high frequency power source 14 so that the potential of the sample electrode 11 can be controlled so that the substrate 5 as a sample has a negative potential with respect to plasma. It has become.

After the substrate 5 is placed on the sample electrode 11, while the temperature of the sample electrode 11 is kept at 20 ° C., the inside of the vacuum vessel 6 is evacuated, and a helium gas is introduced into the vacuum vessel 1 by 50 sccm and a doping material. Diborane (B ₂ H ₆ ) gas as gas is supplied at 3 sccm, and the pressure regulating valve 9 is controlled to keep the pressure in the vacuum vessel 6 at 3 Pa. Next, 800 W of high frequency power is supplied to the coil 13 as a plasma source to generate plasma in the vacuum vessel 6, and 200 W of high frequency power is supplied to the sample electrode 11, so that boron is transferred to the surface of the substrate 5. Can be driven into the vicinity.

Next, the activation process will be described. FIG. 3 shows a cross-sectional view of a laser annealing chamber as an activation chamber in the impurity introduction apparatus used in the first embodiment. As shown in FIG. 3, the laser annealing chamber includes a container 15, a sample table 16, a window 17, an infrared laser 18 as a laser light source, and a mirror 19.
At the time of annealing, the silicon substrate 5 supplied with impurity ions is placed on the sample stage 16, and the surface of the silicon substrate 5 is irradiated with laser light reflected by the mirror 19 from the infrared laser 18, thereby allowing the silicon substrate 5 to be irradiated. The surface of 5 can be activated by heating.

  In the activation process, a flash lamp processing chamber as shown in FIG. 4 can be used as the activation processing chamber. As shown in FIG. 4, the flash lamp processing chamber includes a container 20, a sample stage 21, a window 22, and a flash lamp 23. The silicon substrate 5 supplied with impurity ions is placed on the sample stage 21, and the surface of the silicon substrate 5 is heated and activated by irradiating the surface of the silicon substrate 5 with the light emitted from the flash lamp 23. can do.

  FIG. 5 is a plot of the intrusion intensity of irradiated ultraviolet rays into the silicon substrate in the amorphization step in the depth direction from the silicon substrate surface. FIG. 5 is an example, and is a calculation example for ultraviolet rays having a wavelength of 312 nm. Here, if the depth at which the intensity is 1 / e (e is the base of the natural logarithm) is defined as the penetration depth, 1 / e is about 0.37, so the penetration depth is about 7 nm.

  FIG. 6 is a plot of the penetration depth thus defined versus wavelength. From FIG. 6, it can be seen that the penetration depth is remarkably small in the wavelength region of 100 nm to 380 nm, and the ultraviolet ray is irradiated only to the extremely shallow region of the silicon substrate surface. That is, in order to efficiently amorphize only a very shallow region of the substrate surface, it is preferable that the wavelength of ultraviolet rays in the step of irradiating ultraviolet rays be 100 nm or more and 380 nm or less. A light source having a wavelength of 100 nm or less is very expensive and impractical. Solid materials that can transmit ultraviolet rays of 147 nm or more (those that become the material of the window) include magnesium fluoride, calcium fluoride, lithium fluoride, and the like, since they are available at a relatively low price. It is preferable to use an ultraviolet light source having a wavelength.

  The wavelengths of ultraviolet rays emitted from the Xe lamp are mainly a resonance line of 147 nm and a molecular beam of 172 nm. In other words, the Xe lamp can be used as a light source that can efficiently radiate ultraviolet rays in the above preferred wavelength region at low cost.

  It is also possible to use an excimer laser as an ultraviolet ray source. For example, ArF laser (193 nm), KrF laser (248 nm), or the like can be used.

  Next, as a modification of the first embodiment of the present invention, an impurity introduction apparatus in which an amorphization treatment chamber, an ion supply treatment chamber, and an activation treatment chamber are combined and integrated will be described. FIG. 7 is a schematic plan view of an impurity introduction apparatus according to a modification of the first embodiment of the present invention. As shown in FIG. 7, the impurity introduction apparatus includes an amorphization process chamber 24, a first transfer chamber 25, an ion supply process chamber 26, a second transfer chamber 27, and an activation process chamber 28. And a transfer arm 29 provided in each transfer chamber, and a gate 30 connecting the respective process chambers and transfer chambers. These amorphization process chambers 24, first transfer chambers 25, The ion supply processing chamber 26, the second transfer chamber 27, and the activation processing chamber 28 are linearly arranged. The amorphization processing chamber 24, the ion supply processing chamber 26, and the activation processing chamber 28 are configured in the same manner as those used in the first embodiment.

  In processing using this impurity introduction apparatus, first, a silicon substrate as a sample is first put into the amorphization processing chamber 24. The silicon substrate that has been subjected to the amorphization process is transferred to the ion supply processing chamber 26 by the transfer arm 29 provided in the first transfer chamber 25. The silicon substrate that has been subjected to the ion supply process in the ion supply process chamber 26 is activated by the transfer arm 29 provided in the second transfer chamber 27 (activation process chamber 28 (laser annealing process chamber or flash lamp annealing process chamber). ) And activated.

  Thus, a very efficient processing system can be realized by continuously performing a series of processes.

  In Embodiment 1 of the present invention, the process of making the substrate surface amorphous by irradiation of ultraviolet rays and the process of supplying impurity ions to the surface of the sample can be performed separately, so that economical processing is possible. In addition, deposits and the like on the inner wall of the vacuum vessel in the ion supply processing chamber do not adversely affect the substrate by adhering to the substrate in the amorphization process, so that the amount of introduced impurities can be precisely controlled. Further, since the ultraviolet irradiation intensity gradually decreases in the depth direction of the substrate, the amorphized portion and the crystal portion form a relatively unclear boundary. Therefore, the deep part of the amorphous part (near the boundary with the crystal part) is not excessively heated during the activation process, so that the impurities are prevented from deeply diffusing and the shallow diffusion depth is reduced. The introduction of impurities can be realized.

(Embodiment 2)
Hereinafter, Embodiment 2 of the present invention will be described with reference to FIG.
FIG. 8 is a schematic plan view of the impurity introduction apparatus used in Embodiment 2 of the present invention. In FIG. 8, the impurity introduction apparatus is provided in each of the transfer chambers, the amorphization process chamber 24, the first transfer chamber 31, the second transfer chamber 32, the ion supply process chamber 26, the activation process chamber 28. And a gate 30 connecting the processing chambers and the transfer chambers. The portion where the amorphization treatment chamber 24, the first transfer chamber 31, and the activation treatment chamber 28 are linearly arranged, and the second transfer chamber 32 and the ion supply treatment chamber 26 are linearly arranged is a first portion. The second transfer chamber 32 is branched from the first transfer chamber 31 in a state where the transfer chamber 32 is arranged on the side close to the first transfer chamber 31.

  In processing, a silicon substrate as a sample is first put into the amorphization processing chamber 24. The silicon substrate that has been subjected to the amorphization process is transferred to the second transfer chamber 32 by the transfer arm 29 provided in the first transfer chamber 31. The first transfer chamber 31 is always at atmospheric pressure, but the second transfer chamber 32 is characterized by repeating atmospheric pressure and vacuum. That is, when the substrate is carried into the second transfer chamber 32, the atmospheric pressure state is set, and then the second transfer chamber 32 is evacuated and then transferred to the ion supply processing chamber 26. The substrate after the ion supply process is taken out with the second transfer chamber 32 in a vacuum state, and then transferred to the first transfer chamber 31 after the second transfer chamber 32 is in the atmospheric state. At this time, since the transfer arm 29 of the second transfer chamber 32 is a double arm, the substrate can be taken in and out at a time, so that an extremely efficient processing system can be configured. The substrate carried into the first transfer chamber 31 after being subjected to the ion supply process in this way is transferred to the activation process chamber (laser annealing process) using the transfer arm 29 provided in the first transfer chamber 31. Chamber or flash lamp annealing chamber), and activation treatment is performed.

  In the configuration shown in FIG. 7, both the first transfer chamber and the second transfer chamber repeat atmospheric pressure and vacuum, whereas in the configuration shown in FIG. 8, the second transfer chamber Since only atmospheric pressure and vacuum are repeated, an apparatus configuration capable of performing a series of processing at higher speed can be realized.

(Embodiment 3)
Hereinafter, Embodiment 3 of the present invention will be described with reference to FIG.
FIG. 9 shows a schematic plan view of the impurity introduction apparatus used in Embodiment 3 of the present invention. As shown in FIG. 9, the impurity introduction apparatus is provided in the amorphization processing chamber 24, the transfer chamber 33, the ion supply processing chamber 26, the activation processing chamber 28, and each transfer chamber. It consists of a transfer arm 29 and a gate 30 connecting each processing chamber and transfer chamber. Amorphization process chamber 24, transfer chamber 33, and activation process chamber 28 are linearly arranged, and ion supply process chamber 26 is branched from transfer chamber 33. To do.

  In this impurity introduction apparatus, a silicon substrate as a sample is first put into the amorphization processing chamber 24. The silicon substrate that has undergone the amorphization process is transferred to the ion supply processing chamber 26 by the transfer arm 29 provided in the transfer chamber 33. Then, the substrate on which the ion supply processing is completed in the same manner as in the first embodiment is taken out by the transfer arm 29 provided in the transfer chamber 33, and is activated and activated (chamber or laser lamp annealing chamber). ) And activated.

  In the configuration shown in FIG. 9, since there is only one transfer chamber, an inexpensive device configuration can be realized.

  In the embodiment of the present invention described above, only a part of various variations with respect to the configuration, shape, arrangement, etc. of the processing chamber is illustrated in the scope of application of the present invention. It goes without saying that various variations other than those exemplified here can be considered in applying the present invention.

  Further, although the case where the sample is a semiconductor substrate made of silicon has been exemplified, the present invention can be applied when processing samples of various other materials.

  Further, although the case where the impurity is boron is illustrated, the present invention is effective when the sample is a semiconductor substrate made of silicon, particularly when the impurity is arsenic, phosphorus, boron, aluminum, or antimony. This is because a shallow junction can be formed in the transistor portion.

In addition, the present invention is effective when the doping concentration is low, and is particularly effective as an impurity introduction method aimed at 1 × 10 ¹¹ / cm ^{2 to} 1 × 10 ¹⁷ / cm ² . In addition, as an impurity introduction method aiming at 1 × 10 ¹¹ / cm ^{2 to} 1 × 10 ¹⁴ / cm ² , the effect is particularly remarkable.

  Also, in the ion supply process, the case where the gas supplied into the vacuum vessel is a gas containing a doping material is exemplified, but the gas supplied into the vacuum vessel does not contain a doping material, and the doping material is obtained from solid impurities. The present invention is also effective when it is generated.

  The impurity introduction method and apparatus of the present invention may have a simple apparatus configuration, is economical, can accurately control the impurity introduction amount, and can realize an impurity introduction method and apparatus for forming a shallow impurity diffusion region. In addition to semiconductor impurity introduction processes, the present invention can also be applied to the manufacture of thin film transistors used in liquid crystals and the like, and surface modification of various materials.

Sectional drawing of the amorphization process chamber used in Embodiment 1 of this invention Sectional drawing of the ion supply processing chamber used in Embodiment 1 of this invention Sectional view of the laser annealing chamber used in Embodiment 1 of the present invention Sectional view of the flash lamp annealing chamber used in Embodiment 1 of the present invention Graph showing the depth dependence of the penetration strength of ultraviolet rays into a silicon substrate Graph showing wavelength dependence of UV penetration depth into silicon substrate Schematic plan view of the impurity introduction apparatus used in Embodiment 1 of the present invention Schematic plan view of the impurity introduction apparatus used in Embodiment 2 of the present invention Schematic plan view of the impurity introduction apparatus used in Embodiment 3 of the present invention Sectional drawing which shows the structure of the plasma doping apparatus used in the conventional example Sectional drawing which shows the structure of the plasma doping apparatus used in the conventional example

Explanation of symbols

1 Container 2 Sample stage 3 Window 4 Xe lamp 5 Substrate
6 Vacuum container 7 Gas introduction device 8 Turbo molecular pump 9 Pressure regulating valve 10 High frequency power supply 11 Sample electrode 12 Dielectric window 13 Coil 14 High frequency power supply 15 Container 16 Sample stage 17 Window 18 Infrared laser 19 Mirror 20 Container 21 Sample stage 22 Window 23 Flash Lamp 24 Amorphization chamber 25 First transfer chamber 26 Ion supply chamber 27 Second transfer chamber 28 Activation chamber 29 Transfer arm 30 Gate 31 First transfer chamber 32 Second transfer chamber

Claims (14)

Irradiating the sample with ultraviolet light;
Supplying impurity ions to the surface of the sample;
And a step of heating and activating the surface layer of the sample. The impurity introduction method according to claim 1,
The step of irradiating the sample with ultraviolet rays is a step of irradiating ultraviolet rays having a wavelength of not less than 100 nm and not more than 380 nm. The impurity introduction method according to claim 1,
An impurity introducing method, wherein the step of irradiating the sample with ultraviolet rays is a step of irradiating ultraviolet rays having a wavelength of 147 nm to 380 nm. The impurity introduction method according to claim 1,
The step of supplying the impurity ions includes:
An impurity introduction method comprising: supplying a high-frequency power to a plasma source while supplying a gas containing an impurity element, generating plasma, and supplying impurity ions to the surface of the sample. The impurity introduction method according to claim 1,
The impurity introducing method, wherein the step of activating includes a step of irradiating a laser beam. The impurity introduction method according to claim 1,
The method for introducing an impurity according to claim 1, wherein the step of activating includes a step of irradiating radiation light of a flash lamp. An amorphization chamber that includes an ultraviolet light source, irradiates the sample with ultraviolet light, and amorphizes the surface of the sample;
An ion supply processing chamber that includes a plasma source and supplies impurity ions to the surface of the sample;
An impurity introducing apparatus comprising: an annealing light source; and an activation treatment chamber that activates the surface layer of the sample by heating with the annealing light source. The impurity introduction device according to claim 7,
An impurity introducing apparatus, wherein the annealing light source is a laser light source. The impurity introduction device according to claim 7,
An impurity introducing apparatus, wherein the annealing light source is a flash lamp light source. An impurity introduction apparatus according to any one of claims 7 to 9,
The wavelength of the ultraviolet light source is not less than 100 nm and not more than 380 nm. The impurity introduction device according to claim 10,
The wavelength of the ultraviolet light source is not less than 147 nm and not more than 380 nm. An impurity introduction apparatus according to any one of claims 7 to 9,
The impurity introducing device, wherein the ultraviolet light source is a Xe lamp. An impurity introduction apparatus according to any one of claims 7 to 9,
An impurity introducing apparatus, wherein the ultraviolet light source is an ArF laser. An impurity introduction apparatus according to any one of claims 7 to 9,
The impurity introducing device, wherein the ultraviolet light source is a KrF laser.

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