KR101727677B1 - Laser annealing apparatus and laser annealing method using multiple laser beams - Google Patents
Laser annealing apparatus and laser annealing method using multiple laser beams Download PDFInfo
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- KR101727677B1 KR101727677B1 KR1020150108139A KR20150108139A KR101727677B1 KR 101727677 B1 KR101727677 B1 KR 101727677B1 KR 1020150108139 A KR1020150108139 A KR 1020150108139A KR 20150108139 A KR20150108139 A KR 20150108139A KR 101727677 B1 KR101727677 B1 KR 101727677B1
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- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000005224 laser annealing Methods 0.000 title claims abstract description 28
- 238000000137 annealing Methods 0.000 claims abstract description 70
- 230000001678 irradiating effect Effects 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims abstract description 8
- 239000000758 substrate Substances 0.000 claims description 13
- 239000004065 semiconductor Substances 0.000 claims description 12
- 230000003287 optical effect Effects 0.000 claims description 10
- 239000012535 impurity Substances 0.000 claims description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 10
- 229910052710 silicon Inorganic materials 0.000 description 10
- 239000010703 silicon Substances 0.000 description 10
- 239000000463 material Substances 0.000 description 4
- 239000002131 composite material Substances 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
- 238000005468 ion implantation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/324—Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/26—Bombardment with radiation
- H01L21/263—Bombardment with radiation with high-energy radiation
- H01L21/268—Bombardment with radiation with high-energy radiation using electromagnetic radiation, e.g. laser radiation
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices specially adapted for rectifying, amplifying, oscillating or switching and having potential barriers; Capacitors or resistors having potential barriers, e.g. a PN-junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/66007—Multistep manufacturing processes
- H01L29/66075—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials
- H01L29/66227—Multistep manufacturing processes of devices having semiconductor bodies comprising group 14 or group 13/15 materials the devices being controllable only by the electric current supplied or the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched, e.g. three-terminal devices
- H01L29/66234—Bipolar junction transistors [BJT]
- H01L29/66325—Bipolar junction transistors [BJT] controlled by field-effect, e.g. insulated gate bipolar transistors [IGBT]
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- Microelectronics & Electronic Packaging (AREA)
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- General Physics & Mathematics (AREA)
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- Laser Beam Processing (AREA)
Abstract
A laser annealing apparatus and a laser annealing method using a plurality of laser beams are disclosed. The laser annealing apparatus disclosed in the present application is a laser annealing apparatus for performing a heat treatment by irradiating a laser beam to an object to be processed mounted on a stage and comprises three or more laser light sources for emitting pulsed laser beams, And an image lens unit for irradiating the annealing laser beam emitted from the beam homogenizer to a predetermined region of the object to be processed do.
Description
The present invention relates to laser annealing, and more particularly to a laser annealing apparatus and a laser annealing method using a plurality of laser beams.
In order to fabricate an IGBT (Insulated Gate Bipolar Transistor), which is a type of power device, a predetermined semiconductor process is first performed on the front surface of a semiconductor substrate, then the rear surface of the semiconductor substrate is thinly ground, . Then, an annealing process is performed by irradiating a laser beam on the back surface of the semiconductor substrate in a process for activating impurities after ion implantation.
In order to achieve good activation of impurities by the laser annealing process, it is necessary to be effectively heated to a predetermined depth of the semiconductor substrate by the laser beam. However, since the laser beam used in the conventional laser annealing process has a narrow pulse width, the depth reaching the laser beam inside the semiconductor substrate is small and the time to be heated by the laser beam is short, There is a problem that it is difficult to activate.
According to an embodiment of the present invention, there is provided a laser annealing apparatus and a laser annealing method using a plurality of pulsed laser beams.
In one aspect of the present invention,
A laser annealing apparatus for performing a heat treatment by irradiating a laser beam onto an object to be processed mounted on a stage,
Three or more laser light sources each emitting a pulsed laser beam;
A beam homogenizer that combines the pulsed laser beams emitted from the laser light source to form an annealing laser beam that travels on one optical path; And
And an image lens unit for irradiating the predetermined area of the object with the annealing laser beam emitted from the beam homogenizer.
The depth at which the annealing laser beam reaches the object can be adjusted by changing the interval between the pulses of the laser beams constituting the annealing laser beam.
The time intervals between the pulses of the laser beams are all the same or at least some of the time intervals of the laser beams may be different from other time intervals. Further, the intensity of the laser beams constituting the annealing laser beam may all be the same, or at least some of the laser beams may be different in intensity from other laser beams.
Each of the pulsed laser beams may have a full width at half maximum (FWHM) of 1300 ns or less, for example. The laser annealing apparatus may further include moving means for moving at least one of the stage and the annealing laser beam. The object to be processed may include a semiconductor substrate.
In another aspect,
A laser annealing method for performing a heat treatment by irradiating a laser beam to an object to be processed mounted on a stage,
Emitting three or more pulsed laser beams;
Forming an annealing laser beam that combines the pulsed laser beams to travel through one optical path; And
And irradiating the annealing laser beam onto a predetermined region of the object to be processed.
And moving at least one of the object to be processed and the annealing laser beam.
The depth at which the annealing laser beam reaches the object can be adjusted by changing the time interval between pulses of the laser beams constituting the annealing laser beam. Here, the time intervals between the pulses of the laser beams are all the same, or at least some time intervals of the time intervals of the laser beams may be different from other time intervals. Further, the intensity of the laser beams constituting the annealing laser beam may all be the same, or at least some of the laser beams may be different in intensity from other laser beams.
The impurity implanted into the semiconductor substrate can be activated by irradiation of the annealing laser beam.
According to the embodiment of the present invention, the annealing laser beam, in which the pulses are formed by the combination of the intervals between the pulses, the half width of each of the pulses and the intensity of the beam, etc. according to the annealing condition, Next, the annealing process can be smoothly performed by heating the inside of the object to a desired range.
1 schematically shows a laser annealing apparatus according to an exemplary embodiment of the present invention.
FIG. 2 shows pulses of the first, second, third, and fourth laser beams emitted from the four laser light sources shown in FIG. 1, respectively, with respect to time.
FIG. 3 is a time chart of pulses of the annealing laser beam formed by combining the first, second, third, and fourth laser beams shown in FIG.
FIG. 4 is a graph showing the relationship between the depth of the silicon wafer and the depth of the silicon wafer when the annealing laser beam, which is formed by combining the first, second, third and fourth laser beams emitted from the four laser light sources at regular time intervals between pulses, FIG.
Figure 5 illustrates pulses of an annealing laser beam according to another exemplary embodiment of the present invention.
Figure 6 illustrates pulses of an annealing laser beam according to another exemplary embodiment of the present invention.
Figure 7 illustrates pulses of an annealing laser beam according to another exemplary embodiment of the present invention.
FIG. 8 shows pulses of the first, second, third, and fourth laser beams emitted from the four laser light sources shown in FIG. 1, respectively, in accordance with another exemplary embodiment of the present invention.
FIG. 9 shows the pulses of the annealing laser beam formed by combining the first, second, third and fourth laser beams shown in FIG. 8 in time.
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments illustrated below are not intended to limit the scope of the invention, but rather are provided to illustrate the invention to those skilled in the art. In the drawings, like reference numerals refer to like elements, and the size and thickness of each element may be exaggerated for clarity of explanation. Further, when it is described that a certain material layer is present on a substrate or another layer, the material layer may be present directly on the substrate or another layer, and there may be another third layer in between. In addition, the materials constituting each layer in the following embodiments are illustrative, and other materials may be used.
1 schematically shows a laser annealing apparatus according to an exemplary embodiment of the present invention.
Referring to FIG. 1, the laser annealing
The laser annealing
The first, second, third and fourth
The first, second, third, and fourth laser beams L1, L2, L3, and L4 are arranged such that the first, second, third, and fourth pulses P1, P2, P3, (T1 in Fig. 3). Although not shown in the figure, the sequential emission of the laser beams L1, L2, L3, and L4 can be performed using a predetermined optical element such as an AOM (Acousto-Optic Modulator) or the like. The first, second, third and fourth laser beams L1, L2, L3 and L4 emitted from the
The first, second, third, and fourth laser beams L1, L2, L3, and L4, which are emitted from the first, second, third, and fourth
The
The
In the
FIG. 2 is a diagram illustrating the pulses of the first, second, third and fourth laser beams L1, L2, L3 and L4 emitted from the four
FIG. 3 is a time chart showing a state in which first, second, third and fourth pulses P1, P2, P3 and P4 emitted at a predetermined time interval t1 shown in FIG. 2 are combined . The pulses P1, P2, P3 and P4 shown in FIG. 3 are generated by combining the first, second, third and fourth laser beams L1, L2, L3 and L4, And pulses of the annealing laser beam L. 3, the annealing laser beam L irradiating the
FIG. 4 is a graph showing a temperature distribution according to the depth of a silicon wafer when an annealing laser beam including first, second, third and fourth laser beams emitted from four laser light sources at a constant pulse interval is irradiated onto the silicon wafer Respectively. 4 shows the measured results when the four pulse shapes are all the same, the half width of each pulse is 0.2 mu s (i.e., 200 ns), and the energy density of each of the laser beams is 4 J / cm < 2 & gt ;. Table 1 below shows the maximum temperature according to the depth of the silicon wafer from the results shown in Fig. In Table 1, for example, -6 mu m means a position at a depth of 6 mu m from the surface of the silicon wafer.
Referring to FIGS. 4 and Table 1, the first, second, third and fourth laser beams emitted at a constant pulse interval are combined to form an annealing laser beam having a pulse width broader than that of each of the pulses have. Therefore, the annealing process can be performed by heating the inside of the silicon wafer by reaching the annealing laser beam from the surface of the silicon wafer to a deep depth. Here, by controlling the pulse intervals of the first, second, third and fourth laser beams, it is possible to control the depth at which the annealing laser beam reaches the inside of the silicon wafer, whereby the heat generated by the annealing laser beam The annealing process can be performed by adjusting the range of diffusion.
Figure 5 shows the pulses of the annealing laser beam in time according to another exemplary embodiment of the present invention. FIG. 5 shows a state where four first, second, third, and fourth pulses P1, P2, P3, and P4 sequentially outputted at a predetermined pulse interval t2 are formed in a composite state, The pulses of the first, second, third and fourth laser beams (L1, L2, L3 and L4 in FIG. 1) are combined to form pulses of the annealing laser beam L traveling in one optical path.
5, the first, second, third, and fourth pulses P1, P2, P3, and P4 are sequentially emitted at a constant time interval t2, 3 is larger than the interval t1 between the pulses shown in Fig. Thus, the annealing laser beam L including the pulses P1, P2, P3, and P4 of the type shown in Fig. 5 is incident on the surface of the
In the above embodiments, the four pulses P1, P2, P3 and P4 are outputted at a constant time interval t1 or t2. However, the pulses P1, P2, P3 and P4 May vary in various ways.
Figure 6 illustrates pulses of an annealing laser beam according to another exemplary embodiment of the present invention. 6, the first, second, third, and fourth pulses P1, P2, P3, and P4 that are sequentially emitted while varying the intervals between pulses are formed in a composite state. P1, P2, P3, and P4 are formed by combining the first, second, third, and fourth laser beams (L1, L2, L3, and L4 in FIG. 1) to form pulses of an annealing laser beam .
Referring to FIG. 6, the first, second, third, and fourth pulses P1, P2, P3, and P4 are sequentially output at predetermined time intervals. Here, the interval t1 between the first pulse P1 and the second pulse P2, the interval t2 between the second pulse P2 and the third pulse P3, and the interval t2 between the third pulse P3 and the fourth pulse The intervals t3 of the pulses P4 may be different from each other. 6, the first, second, third, and fourth pulses P1, P2, P3, and P4 have the same shape. However, the first, second, third, Some of the fourth pulses P1, P2, P3, P4 may have a different form from the other pulses.
Figure 7 illustrates pulses of an annealing laser beam according to another exemplary embodiment of the present invention. FIG. 7 shows the first, second, third, and fourth pulses P1, P2, P3, and P4 sequentially formed at different time intervals t1. These pulses P1, P2, P3 and P4 are generated by combining the first, second, third and fourth laser beams (L1, L2, L3, L4 of FIG. 1) And pulses of the laser beam L.
Referring to FIG. 7, the first, second, third and fourth pulses P1, P2, P3 and P4 are sequentially output at a predetermined time interval t1. Here, the second and fourth pulses P2 and P4 may have different forms from the first and third pulses P1 and P3. More specifically, the pulse width W1 of the second and fourth pulses P2 and P4 may be different from the pulse width S2 of the first and third pulses P1 and P3, have. 7 illustrates an example in which four pulses P1, P2, P3, and P4 are output at the same time interval t1. However, some pulse intervals may be different from other pulse intervals.
FIG. 8 shows pulses of the first, second, third, and fourth laser beams emitted from the four laser light sources shown in FIG. 1, respectively, in accordance with another exemplary embodiment of the present invention. 9 shows the pulses of the annealing laser beam formed by combining the first, second, third, and fourth laser beams shown in FIG. 8 with time.
Referring to FIG. 8, the first, second, third and fourth laser beams L1, L2, L3 and L4 emitted from the four
As described above, the annealing laser beam, in which the pulses are formed by a combination of the pulses, the half width of each of the pulses, and the intensity of the beam, according to the annealing condition, reaches the desired depth in the object, The annealing process can be smoothly performed by heating the inside of the object to a desired range.
While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined by the appended claims.
100 .. Laser annealing device
101. A first laser light source
102. A second laser light source
103. Third laser light source
104. The fourth laser light source
200 .. reflection mirror
300 .. Beam homogenizer
400 .. Imaging Lens Unit
L1 .. First laser beam
L2 .. Second laser beam
L3 .. Third laser beam
L4 .. Fourth laser beam
L .. annealing laser beam
W .. The object to be processed
S .. Stage
Claims (15)
Three or more laser light sources each emitting a pulsed laser beam;
A beam homogenizer that combines the pulsed laser beams emitted from the laser light source to form an annealing laser beam that travels on one optical path; And
And an image lens unit which irradiates the annealing laser beam emitted from the beam homogenizer to a predetermined region of the object to be processed,
And adjusts the depth at which the annealing laser beam reaches within the object by changing the distance between the pulses of the laser beams constituting the annealing laser beam.
Wherein the time intervals between the pulses of the laser beams are all the same or at least some time intervals of the time intervals of the laser beams are different from other time intervals.
Wherein the intensity of the laser beams constituting the annealing laser beam are all the same or at least some of the laser beams are different in intensity from other laser beams.
Wherein each of the laser beams includes a pulse having a full width at half maximum (FWHM) of 1300 ns or less.
And moving means for moving at least one of the stage and the annealing laser beam.
Wherein the object to be processed comprises a semiconductor substrate.
Emitting three or more pulsed laser beams;
Forming an annealing laser beam that combines the pulsed laser beams to travel through one optical path; And
And irradiating the annealing laser beam onto a predetermined region of the object to be processed,
Wherein the depth of reach of the annealing laser beam in the object is adjusted by changing a time interval between pulses of the laser beams constituting the annealing laser beam.
And moving at least one of the object to be processed and the annealing laser beam.
Wherein the time intervals between the pulses of the laser beams are all the same or at least some of the time intervals of the laser beams are different from the other time intervals by a laser annealing method
Wherein the intensity of the laser beams constituting the annealing laser beam is all the same or at least some of the laser beams are different in intensity from other laser beams.
Wherein each of the laser beams comprises a pulse having a half-width (FWHM) of 1300 ns or less.
Wherein the object to be processed comprises a semiconductor substrate.
And impurities injected into the semiconductor substrate are activated by irradiation of the annealing laser beam.
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KR102238080B1 (en) | 2019-11-27 | 2021-04-08 | 인하대학교 산학협력단 | Laser Annealing Apparatus and Method |
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KR20210057265A (en) * | 2019-11-11 | 2021-05-21 | 삼성전자주식회사 | laser annealing apparatus and manufacturing method of semiconductor device using the same |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2001185504A (en) * | 1999-12-22 | 2001-07-06 | Sanyo Electric Co Ltd | Laser anneal method and device |
JP2003037079A (en) * | 2001-07-23 | 2003-02-07 | Japan Steel Works Ltd:The | Method and device for irradiating laser light |
JP2003229376A (en) * | 2001-11-30 | 2003-08-15 | Semiconductor Energy Lab Co Ltd | Laser irradiating device and method, and method for manufacturing semiconductor device |
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Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
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JP2001185504A (en) * | 1999-12-22 | 2001-07-06 | Sanyo Electric Co Ltd | Laser anneal method and device |
JP2003037079A (en) * | 2001-07-23 | 2003-02-07 | Japan Steel Works Ltd:The | Method and device for irradiating laser light |
JP2003229376A (en) * | 2001-11-30 | 2003-08-15 | Semiconductor Energy Lab Co Ltd | Laser irradiating device and method, and method for manufacturing semiconductor device |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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KR102238080B1 (en) | 2019-11-27 | 2021-04-08 | 인하대학교 산학협력단 | Laser Annealing Apparatus and Method |
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