TW200529327A - Laser thermal annealing of lightly doped silicon substrates - Google Patents

Abstract

Apparatus and method for performing laser thermal annealing (LTA) of a substrate using an annealing radiation beam that is not substantially absorbed of long wavelength radiation (1 micron or greater) in some substrate, such as undoped silicon substrates, is a strong function of temperature. The method includes heating the substrate to a critical temperature where the absorption of long-wavelength annealing radiation is substantial, and then irradiating the substrate with the annealing radiation to generate a temperature capable of annealing the substrate.

Description

200529327, IX. Description of the invention: C. The technical leader of the invention] This application is a part of the US patent application (No. 10 / 674,106) filed on September 29, 2003 to continue the application. 5 Field of the Invention The present invention relates to a device and method for laser thermal annealing for laser thermal annealing, and in particular, to a substrate that does not efficiently absorb annealing radiation at ambient temperature. L Prior Art] Background of the Invention Laser thermal annealing or LTA (also known as "laser heat treatment,") is a technique used to rapidly raise and lower the temperature of a substrate surface to produce a change in properties. An embodiment may include Anneal and / or activate dopants in the source, drain or gate regions of transistors used to form integrated devices or circuits. LTA can also be used to form silicide regions in integrated devices or circuits at 15 To reduce the resistance of the polycrystalline silicon flow channel, or trigger a chemical reaction to form or remove substrate (or wafer) substances. LTA offers the possibility to accelerate the annealing cycle by 1000 times compared to traditional annealing techniques, so it is practically eliminated The diffusion of doped impurities used in Shixi wafers during the annealing or activation cycle. This results in a steeper doping profile, 20 and in some cases a higher degree of activation. This will cause integrated circuits Has better performance (such as faster). Us Patent Applicati Serial No. 10/287 864 reveals the use of laser 2 for LTA__ substrate. The laser correction is focused to a narrow line, which is in- Raster pattern and at a fixed speed Concealed across the substrate. 5 and more: This is only useful in relatively heavily doped substrates (ie about 3x10 η atoms / cm3 or more y table / degree), which is used in lasers doped with silicon. The radiation absorption length is small P = approximately and the thermal diffusion length scale. Conversely, for light substrates (ie, doping concentrations of 5: 1016 atoms W or less), the light of the co2 laser will pass through the substrate. It does not give considerable energy to the substrate. Therefore, what is needed is to use a CO2 laser light having a wavelength of 10.6 μm to pass through the substrate without heating, to efficiently perform lightly doped Shixi substrates. _ [Summary of the invention] Summary of the invention 10 Turning the light—viewing the device for heat treatment-having a surface of the substrate. The device includes-a thunder that can generate continuous annealing radiation with a wavelength that is not substantially absorbed by the substrate at room temperature. The device also includes an annealing optical system adapted to obtain the annealed light and form-anneal light, which forms a first image on the substrate surface, and wherein the first image sweeps across the surface of the 15 substrate. The delta device further includes at least one portion for heating the substrate. To • —Critical temperature heating element 'makes the annealed light incident on the heated part and absorbed by the surface near the substrate during cat sweeping. A specific example can be used-short-wavelength laser diode light immediately Long-wavelength annealing is performed before light irradiation to complete the heating of a part of the substrate. Another method of laser thermal annealing-substrate is invented by the company. The method includes a method of providing a substrate that does not have a large amount at room temperature. Lasers of the wavelength absorbed by the substrate provide -annealed radiant light, and heat at least a portion of the substrate to a -critical temperature 'so that light at the annealing can be absorbed in a large amount on the surface near the substrate in the heated portion. The method also includes Annealing light shot 6 200529327 Before the substrate, immediately heat a part of the surface of the substrate to start self-maintaining annealing. Brief Description of the Drawings Figure 1A is a cross-sectional view of a specific embodiment of an LTA device according to the present invention. It includes an LTA optical system and a silicon substrate processed by the system. The LTA device includes a heated chuck to support and The substrate is heated, and an optional thermal barrier surrounds the chuck to reduce light transmission to other devices and promote substrate heating efficiency. Figure 1B is a specific embodiment 10 of the LTA device of the present invention similar to Figure 1A. A cross-sectional view includes a heating kit for preheating the substrate around the substrate; FIG. Ic is a cross-sectional view of a specific embodiment of the LTA device of the present invention similar to FIG. 1A, in which the heated chuck and the The selected insulation barrier is replaced by an optical heating system, which is suitable for preheating at least a part of the substrate 15 with preheating radiant light; 1 Figure 2 shows the annealing light of a wavelength of 10.6 μm on a non-doped stone substrate Absorption length LAbm) vs. substrate temperature Tsfc), and diffusion length LdWhi) vs. substrate temperature TsfC) at 200 dwell time; Figure 3 is a computer simulation of substrate temperature with depth (μιη) and annealing radiation Light 2〇 Set (μΠ1) as a function curve, which shows the "hot spots" formed on the substrate by the annealing radiation accompanied by self-maintained annealing; Figure 4A is a schematic diagram showing the position of the substrate surface as a function in an embodiment The relative intensity and light curve of preheating and annealing radiation; Figure 4B is an enlarged cross-sectional view of the substrate. It illustrates how the heat from the preheating wheel 150 in the square of annealing radiation light before 2005 200529327 can promote the substrate to the annealing radiation. The self-sustained annealing state is maintained by absorption of light; FIG. 5 shows the highest substrate temperature Tμαχ (° c) generated by irradiating a heavily doped silicon substrate with annealing radiation having a wavelength of 10.6 μηι, and the incident energy P1 of the annealing radiation 5 (W / cm); Figure 6 is the maximum substrate temperature obtained by two-dimensional finite element simulation

Tmax (C) 'plot of the initial temperature of an annealed substrate with annealed radiant light at different incident energies; Figure 7 shows the absorption length of 780nm preheated radiant light Α (μιη) vs. substrate 10 temperature Ts ( Figure t :); Figure 8A is a cross-sectional view of a specific example of the optical replacement system of Figure 1C, which is a diagram on the YZ plane; Figure 8B is a specific example of the optical replacement system of Figures 1C and 8A The cross-sectional view of the example is a view on the XZ plane; Figure 9A is an enlarged sectional view of the heating radiation source and the cylindrical lens array in the X_z plane; Figure 9B is an enlarged view of the heating radiation source and the cylindrical lens array in the γ_ζ plane. Sectional view; Figure 10A is a simplified enlarged view of the pre-heating radiation source, the replacement lens and the pre-heating radiation light incident on the substrate perpendicular to the substrate, and includes a polarizer and the pre-heating radiation light arranged to reduce the reflection and Return to the quarter-wave plate of the pre-heating radiation amount of the pre-heating radiation source; Figure 10B is a magnified image of the pre-heating wheel radiation source, the continuation lens and the pre-heating Kota light incident on the substrate perpendicularly incident. Includes a polarizer and pre-heated light 8 200529327 light to reduce A Faraday rotator with less scattering from the substrate and the amount of preheated transmission back to the preheated radiation source; Figure 11 shows the reflectance difference R (%) for pure stone and thick sound on a silicon substrate is 300nm, 4 OOnm and 500nm field oxide film examples of the incident angle 5 θ] 50 (degrees); Figure 12 is similar to Figure 11, a graph showing a 130nm thick layer of polycrystalline stone and The reflectivity of the oxide layers with thicknesses of 300 nm, 400 nm, and 500 nm on the substrate, respectively; FIG. 13 is an enlarged schematic diagram of Embodiment 10 of the LTA device similar to FIG. 10B of the present invention, but it includes a configuration to obtain reflection preheating Circulating optical system 300 which radiates 150r and guides it back to the substrate 300; FIG. 14 is a cross-sectional view of a specific example of the cyclic radiating light system implementation of FIG. 13, which includes a rectangular mirror and a collection / focusing Lens; FIG. 15 is a cross-sectional view showing the deformation of the specific embodiment in FIG. 14, where the right-angle mirror is unfolded (offset) by one from the axis A3, resulting in a gap between direct incidence and cyclic preheating light The incident angle deviates; FIG. 16 is another example of the circular optical system in FIG. 13 A cross-sectional view of a specific example, which includes a collecting / focusing lens and a grating; FIG. 17 is a simplified cross-sectional view of a configuration example of a specific embodiment for preheating a substrate, which uses similar angles of incidence from both ends of the substrate normal Both preheat optical replacement systems. The different components described in the drawings are for representation purposes only and are not drawn to scale. Certain portions may be enlarged, while others may be reduced. These drawings are used to illustrate different implementation methods of the present invention, which can be understood and used by those skilled in the art. [Goods] Detailed description of the preferred embodiment The present invention relates to laser thermal annealing (LTA) of a substrate, and is particularly related to an apparatus and method for LTA of a 5-fine wafer (substrate). The term "changing impurities" herein refers to a doping concentration of about 10] 6 atoms / cm3 or less. The doping concentration in the substrate is related to the general production of the substrate to achieve the desired resistance and the substrate type (ie, N-type or type). In the following detailed description, the general method of an LTA device of the present invention and the "self-sustained annealing state" produced by the present invention are described. This is a specific example accompanying various different embodiments of the present invention. Several graphs of different substrates / JHL degrees show the main properties of the radiation absorbed by the silicon substrate to explain. Then explain the method of determining the appropriate energy level in the preheated radiant light, and then use it to implement specific examples and preheating. The heating lens of the substrate is heated by the radiation light. The details and orientation of the radiation light and the orientation of the radiation light are detailed. I. General UA device Figure 1A is a specific example of the LTA device 8 of the present invention and will be used. A cross-sectional view of an annealed substrate 10. The substrate 10 has an upper surface 12 and an integrated (bulk) region 16, which is undoped ", or more strictly, it typically contains very Very small junction areas or components with high doping levels are lighter doped. The reference letter N refers to the normal to the upper surface 12. In an implementation variant, the substrate 10 is a wafer. The LTA device 8 includes an LTA optical system 25 having an annealing radiation source 26 and an LTA lens 27 arranged along the optical axis A1. The lens 27 obtains continuous (ie, non-pulse) annealing radiation 18 from the annealing radiation source 200529327 26 and generates a continuous annealing radiation 20 to form an image 30 (such as a line image) on the substrate surface 12. The annealing radiation light 20 is incident on the higher surface 12 at an angle of incidence 020 with respect to the surface normal n and the optical axis A1. 5 The arrow 22 indicates an exemplary moving direction of the annealing radiation light 20 relative to the substrate surface I2. The substrate 10 is supported by a chuck 28, which in turn is supported by a movable stage MS, which is operatively connected to a stage driver 29, which causes the stage (and therefore the substrate) to be selected Speed and relative to the direction of the annealing radiation 20 or other reference. The scanning movement system 10 of the movable stage ms is indicated by an arrow 22 '. In one embodiment, the stage ms can be moved at least in two dimensions. In an embodiment, the LTA device 8 includes a reflected radiation monitor M1 and a temperature monitor] ^ 2. The reflected radiation monitoring gM1 is configured to obtain radiation reflected by the substrate surface 12, as shown by radiation 20R. The temperature monitor 15 M2 is configured along the surface normal N to measure the temperature of the substrate surface 12. In one embodiment, the temperature monitor 15 M2 is configured along the surface normal N to be incident on an image 30 formed by the annealing radiation light 20. Observe at or near the normal. The monitor M1 & M2 is connected to a controller (which will be described later) and provides feedback control based on the measured reflected radiation 20R and / or the measured substrate surface 12 temperature, as described in more detail below 20 °. In the embodiment, the LTA device 8 further includes a monitor unit operatively connected to the annealing light source 26, the stage driver 29, and the selection monitor M3 as the incident energy monitor included in the lens 27.口 移 的 控制 32。 The mouth moving controller 32. The controller 32 may be a microprocessor connected to a memory, or 11 200529327 a microcontroller, a programmable logic array (PLA), a field effect programmable logic array (FPLA), a programmable array logic (PAL), or other Control element (not shown). The controller 32 can operate in two modes: 丨) an open loop, in which the hold-fixed energy is transmitted to the substrate 10 at a fixed 5 scan rate via the stage drive, through the back-field shooting; and 2) the closed loop , Where the highest temperature is maintained-fixed on the substrate surface 12, or held_fixed in the substrate to absorb energy. This maximum substrate temperature changes directly with the absorbed energy and is inversely proportional to the square root of the cat sweep speed. In one embodiment, the closed loop control is used to keep the ratio of the square root of the absorbed energy and the scanning speed of the incident light 20 incident on the substrate in the annealing zone 10 fixed. That is, if P20 is the amount of energy of annealing light 20, and ρ30 is the energy of reflection, then the absorbed energy is Pa = P20-p30. If the sweeping speed of the substrate is V relative to the annealed light, the ratio _ / 2 is fixed to maintain the temperature indirectly. 15 According to the closed-loop operation of directly measuring the highest temperature, the controller 32 obtains a signal (such as an electronic signal), as if by temperature monitoring, via the southmost substrate temperature of the signal = 2, and controls the human injection energy or sweep rate to maintain a maximum Substrate temperature. The absorbed energy ^ is obtained by annealing the light incident light of the sampled portion with annealed light of 20 incident energy, and subtracting the reflected light of the signal S1 generated by the reflection 20 round mirror M1 to reduce the energy ho. In addition, the controller 32 is adapted to calculate parameters based on the obtained signal and the number of turns in (such as the amount of energy to be absorbed and the retention time. The controller 32 is also connected to be operated by an operator or by ^, Fly from a larger component or part of the process tool (not shown) to get one, ») line] Shuowaixun No. S3. This parameter indicates the amount (size) of the annealing radiation 20 which provides 12 200529327 to process the substrate or the desired maximum substrate temperature. The parameter signal may also indicate the intensity, scan rate, scan speed, and / or scan number of a predetermined amount used to transmit the annealing radiation 20 to the substrate 10. 5 In an embodiment, the annealing radiation source 26 is a C02 laser, so the annealing wheel light 20 has a wavelength of ι0.6 μm. However, the general annealing radiation source 26 may be any continuous radiation source, and its radiation has a wavelength that is not absorbed by the substrate at room temperature, but when the substrate, or a sufficient portion of the substrate top, is relatively large at a higher temperature, Absorbed by the same substrate. 10 LTA device 8 is suitable for having the advantage of annealing and radiating light 20 absorbed near the top end of the substrate to efficiently raise the temperature of the top end of the substrate, while the temperature of the substrate body is completely constant. In other words, when the substrate is a semiconductor wafer, the present invention directly increases the temperature at which the surface of the wafer is formed on or near a component (such as a transistor), rather than heating the wafer body. 15 However, lightly doped and undoped substrates are not easy to anneal at ambient temperature because long-wavelength radiation passes through the substrate without significantly heating the top surface. On the other hand, annealing of heavily doped substrates is not difficult, because the incident annealing burst is absorbed by the material at about 100 microns and increases its temperature to the desired annealing temperature. 20 The body (bulk) region 16 of the substrate 10 does not absorb a large amount of radiation by light and is not heated. It is used to rapidly cool the top surface region when the annealing radiation light 20 is no longer provided to the substrate. The advantage of the present invention is that under certain infrared wavelengths, such as a CO2 laser with a wavelength of 10.6 μm, the light-doped stone is strongly related to the substrate temperature. When a large amount of annealed radiant light is absorbed, the substrate surface temperature increases, which causes stronger absorption, which in turn causes stronger heating on the substrate surface, and so on. 11Self-sustained annealing state Figure 2 is a graph of the absorption length of λ0.6 μm radiation on a silicon substrate (5 L.m) (vertical axis) versus substrate temperature TS (° C). The point also included in the figure is the diffusion length at 200 μδ dwell time [as a function of substrate temperature. The absorption length is a depth required to reduce the intensity of the annealing radiation light 20 to 1 / e. The thermal diffusion length LD is the depth at which the surface temperature transiently rises and is transmitted to the material at certain dwell times. Note that ^ and 1 ^ have approximately the same value ~ 60μηι at a temperature of 1 ^ ~ 600 ° C. The absorption length 1 ^, which strongly changes with the substrate temperature Ts, produces two stable states, namely: (1) the annealing radiation 20 passes through the substrate without being absorbed in a large amount, and therefore does not generate a large amount of heating, Or (2) The annealing radiation light 20 is largely absorbed near the substrate surface 12, so it is generated on the substrate surface 15 or below the image 30 relative to the image 30, which is generated as the annealing radiation light 20 moves uniformly on the substrate surface (ie, scanning). A "hot spot, '. Figure 3 is a computer-simulated curve of the substrate temperature (° 0 as a function of depth (μηι) and annealing radiation position (μηι). The temperature curve is a hot spot (shown by 31) that passes through the substrate Inside and across the substrate surface 12. The moving hot spot 31 uses 20 thermal diffusion to preheat the area of the substrate 10 in front of the image 30 (see Figure 4B, described below). The preheating of the substrate together with the propagation of the hot spot 31 can The radiation in the annealing radiation light 20 is more efficiently absorbed than the upper surface 12 when the radiation scans the surface of the substrate. The steady state (2) is generated by the pursuit of the device 8 and the accompanying method of the present invention, and This is called "self-sustained annealing state, '. 200529327 A general method for generating a self-sustained annealing state according to the present invention includes heating the substrate 10 (or a selected region or part thereof) to a critical temperature Tc (such as 350 ° C or higher). , As explained in more detail below), so that the annealing radiation is greatly absorbed by the substrate, that is, the point at which the self-sustained annealing state starts. 5 The precise Tg value is based on the temperature distribution in the substrate, and its doping The material concentration and the light intensity of the annealing are determined. Therefore, in an embodiment, the critical temperature Tc is determined by experience. This may include, for example, measuring the temperature of an annealing radiation at different initial temperature states or a fixed initial temperature. Temperature test substrate, and the highest temperature of 10 degrees generated by different annealing or preheating light intensity. The preheating of the substrate 10 can be increased in several ways to increase the self-sustained annealing state. Several include heating elements used to heat the substrate 10 To implement the method of generating a self-sustained annealing state in the light-changing substrate 1G, and to implement a purpose-like LTA device 8 HL has a heat-shielding screen P. Example 15 of early heating and losing disks. See also Figure 18. In the embodiment, the chuck 28 has thermal conductivity and includes a heating element connected to the power supply 52. 50. The power supply is sequentially connected to and controlled by the controller 32. A heat-insulating layer 53 surrounds the bottom and sides of the chuck 28 to limit undesired heating of the stage and heat from the lost disk. Loss. At the time of operation, the controller 32 causes the power supply 52 to operate, which sequentially supplies power to the heating element 50. The heating element 50 generates heat 56 to respond. In a practical example D, the generated heat The amount of 56 is controlled in the chuck and operatively connected to the power supply 52 (or an alternative controller 3 to take a temperature sensor ^), so that the chuck temperature is limited to a certain, predetermined Maximum 15 200529327 temperature. When the substrate is mounted on the chuck, its temperature quickly reaches the same temperature as the chuck. Typically. The chuck temperature TCH is about 400 ° C. In another embodiment, the device 8 also optionally includes a thermal barrier 62 supported above the substrate 12 to reflect heat 56 back to the substrate. This results in more uniform heating of the substrate and less heating of device components at the other end of the barrier. In one embodiment, the thermal barrier 62 includes an aperture 64 to allow the annealing radiation 20 to reach the surface 12 of the substrate 10. _ IV. Specific examples of heating kits According to FIG. 1B, in another specific embodiment, the device 8 includes an internal space 82 having a size large enough to surround the substrate 10 and the chuck 28 or the substrate, the chuck and the carrier. MS heating kit 80 (such as a furnace). The kit 80 includes an additional heating element 50 connected to the power supply 52 (especially a heating assembly included outside the chuck 28). The power supply 52 is connected to the controller 32. In the embodiment, the 'kit 80 includes a window or aperture 84 to allow the annealing radiation 20 to reach the surface 12 of the substrate 15. As described above, the heat insulation layer ^ illustrated in Fig. 1A is also present on the chuck side S or bottom than φ ^ to limit the undesired heat loss from the chuck to the stage. During operation, the controller 32 activates the power supply 52, which sequentially supplies power to the heating element 50. The heating element 50 generates heat 56 in response, thus raising the temperature of the 20-inch chuck to the substrate and its surroundings to. (3) The highest critical temperature Tc kit 80 | λ is preferably adiabatic, so that the heat 56 is still transferred to the centimeter space μ, thus promoting the efficiency and uniformity of the substrate heating. V For specific examples of preheating radiation, see Figure 1C in Canga. In another embodiment, the device 8 includes-16 200529327 preheating optics with a preheating radiation source 142 and a replacement lens 143 arranged along the optical axis A2. Alternative system 140. The pre-heating radiation source 142 is to radiate radiation 147 to provide pre-heating radiation light 150 for the replacement lens 145 before the substrate is heated by the annealing radiation light, and thereby to preheat the substrate. The radiation 147 has a wavelength that is easily (largely) absorbed by 100 | 1111 5 or less silicon. In a specific embodiment, the preheat radiation source 142 is a laser diode array that emits preheat radiation 147 with a wavelength of 0.8 [im (800 nm) or 0.78 μm (780ηΓη). The following describes a replacement lens 143 in a specific example. The preheating radiation source 142 and the replacement lens 143 are operatively connected to the monitors M1 and M2, and the stage driver 29 shown in FIG. 11a is connected to the controller 10. For ease of explanation, they are not shown in FIG. . In operation, the preheating radiation source 142 emits radiation light 147, which is obtained by replacing the lens 143. The replacement lens 143 generates radiant light, and the scale forms an image 160 (such as a line image) on the substrate surface 12. The preheated radiated light 15 is incident on the substrate surface 12 at an incident angle θ] 5 () measured with respect to the substrate normal N. 15 纟 —Implement a specific example, the image 30 formed by the annealing sister light 20 and the scene φ formed by the pre -..., Koda shot light 150 image 16 are arranged on the substrate surface I2, as shown in FIG. Therefore, preheating the light emission light 15 as a regional pre-… part or area of the xuan substrate that is to be irradiated by the annealing wheel light 20. The arrow 22 does not move in the direction of the substrate 10 (such as via a movable plate ^; see Figure 1). In the specific example, 208 is a fixed light beam and a light beam (or equivalent to a mouth light ~ like 3G) And _) move to perform these lights (or images). In another example, Lai radiation 150 and annealing radiation 20

Deliberately redundant 'as in the 1 / e2 intensity profile of each light intensity curve, as shown in Figure 4A. 17 200529327 FIG. 4B is an enlarged cross-sectional view of a specific example in which the substrate is irradiated with light 20 and 150. Fig. 4B illustrates how the heat of the preheated radiation 150 in front of the annealing radiation 20 promotes the absorption of the annealing radiation near the top end of the substrate surface. The heat 166 from the preheated radiated light 150 diffuses into the substrate 10 in front of the annealed light 20. When the radiation light is moved relative to the substrate, as shown by arrow 22, the annealing wheel light 20 enters the area (ie, the substrate portion) that is first heated by the preheating radiation light 150. This process is used to increase the temperature of the substrate at or near the substrate surface beyond the critical temperature Tc. This allows the annealing radiation 20 to be efficiently absorbed by the substrate, as shown by the absorption annealing radiation 20 (dotted line). The relatively rapid absorption of the absorbed annealing radiation 10 light 20 'near the substrate surface 12 of the substrate 10 is used to rapidly increase the substrate surface temperature to a maximum value at the end of the annealing light emitted at 5 ° C to an annealing temperature TA (such as about 1600. This results in annealing of selected regions, such as activating dopants implanted on the top surface of the substrate surface. VL substrate temperature Figure 15 Figure 5 is the highest substrate produced by irradiating a heavily doped silicon substrate with 10. ^ m radiation Temperature TMAXfc), a graph of the incident energy Pi (w / cm) of the radiation. This data is obtained using a one-dimensional finite element simulation program. The simulation assumes an infinitely long annealed light beam. Therefore, this light energy is measured in Watts / cm rather than watts / cm2. The simulation also assumes that the annealing radiation 2020 has a Gaussian light waveform with a half-width of 120 μπ1, and scans across the upper surface of the substrate at a speed of 600 mm / s, resulting in a 200 μδ dwell time. Here, the "dwell time" is the length of time that the image 30 produced by the annealing radiation light 20 stays at a specific point on the substrate surface 12. In this case, the figure shows the biP] and the temperature of the substrate in the south of the South Korea. Is a linear relationship. Because the two-dimensional 18 200529327 model assumes that the annealing radiation 20 is infinitely long, there is no energy loss at the end of the online image 30.-Limiting the length of the light will cause some additional heat loss at the end of the light. As a result, the given incident energy P! Has a lower maximum temperature. Figure 5 shows an absorbable (ie, highly doped) substrate. In some specific cases, a person's injected energy of about 50_em will be the highest. The substrate temperature ^ TMAX is raised from ambient temperature to 427 ° C. This is about the same as 115 ° w / cm, which raises the temperature to the melting point of silicon at 1410 ° C. The relationship shown in Figure 5 is similar to that of annealing radiation 20 Preheated radiant light 150 with the same width and dwell time. In both cases, thermal diffusion is the main mechanism of 10 thermal distribution. A substrate temperature Tmax peak at 400 ° C does not produce a uniform Annealing radiation of substrate temperature TS400 ° C 20 The absorption is almost the same, because of the former temperature distribution, the distance within the substrate approximately equal to the thermal diffusion length 1 ^ has dropped to the ambient temperature. Figure 6 shows the maximum substrate temperature TMAX (° C). The incident energy 15 P] is the graph of the initial radiation temperature of the annealed radiant light 20 on the undoped silicon substrate. This is also obtained from a two-dimensional finite element model. When the temperature is lower than about 327 ° C, incident radiation is hardly generated. Influence, and the maximum substrate temperature Tmax (C) is equal to the initial substrate temperature T !. In other words, the annealed light 20 passes through the substrate 10 and does not significantly heat the substrate. However, at a temperature between 377 20 ° and 477 ° (: The initial substrate temperature is that a large amount of annealing radiation light 20 absorption occurs, which is based on the incident energy P in the annealing radiation light]. This result is a steepest increase in the temperature Tmax of the southernmost substrate. When high absorption occurs , High temperature change, the maximum temperature Dmax will increase more linearly when irradiated by annealing radiation light 20. Note that the unit of energy used in Figures 5 and 6 is watts per centimeter 19 200529327 5

10 15

(W / cm). This energy means the energy per unit length of the scanned image (such as a line image) contained between half-energy points. Therefore, the energy of the shadow of -⑽I has a width of the lion with respect to the average intensity of -95,833 W / em >. In order to produce a self-sustained annealing state, the temperature generated by the preheating radiation source 142 is required to heat the substrate to a critical temperature Tc, which can be calculated from the information in the figure. The figure here refers to the fact that when the substrate reaches an average hook temperature of about 4271, the substrate temperature TMAX which has increased substantially indicates the beginning of the self-sustained annealing state. If a laser diode source is used to provide the required preheating, it can be predicted—a significantly higher temperature, in Figure 7 is a graph of the temperature of the substrate at the absorption length of 78Gnm radiation at the undoped slave absorption length. The absorption characteristics are very similar to those at 78 nm. It can be seen that even if the length of the series LA at room temperature is about 10 mm, it is short enough to ensure that the surface area of the substrate can be efficiently heated and the temperature distribution of 200 μδ and above is mainly determined by thermal diffusion. In order to obtain efficient C02 laser% (such as annealing light 20) absorption on an undoped stone substrate with an uneven temperature distribution, as if it were generated by a laser diode source (such as used to generate preheated light) 15 °), a temperature was measured relative to the absorption length of approx. This is achieved by a substrate temperature of about 5 thief and a 20 TMAX peak. Referring to FIG. 5 again, the maximum substrate temperature of t may require about 600 W / cm (50,000 W / cm2) of energy for preheating light emission] 50. V7 / · Determining the energy of the preheating radiation light 150 It is actually easy to determine the minimum energy of the preheating radiation light 150 to efficiently combine the annealing radiation light 20 to the substrate. In an implementation with 20 200529327, when the annealing radiation 20 is set to fully anneal the energy of an absorbable substrate, the substrate that does not absorb much of the wavelength of the annealing radiation 20 at room temperature is preheated by the radiation 150 and annealed. The irradiated light 20 was irradiated. The preheated radiant light of 15 ° is increased until the annealing temperature is detected on the substrate. This can be achieved by measuring the substrate temperature with the temperature monitor M2 as shown in Fig. 51A.

The anneal radiant light and the substrate change from a little or nothing, to a sudden and effective phase coupling with the substrate. If the temperature of the substrate is too low, it will not change to the annealing temperature or a sudden change to the melting point of the substrate will occur. As the temperature of the substrate increases further, there will be a narrow range of annealing energy, which allows stable operation at temperatures below the melting point. Increasing the substrate temperature further increases the range of annealing energy and relative annealing temperature range. Therefore, there is no precisely defined energy of the preheated light beam 150 to anneal the radiation at the substrate at the beginning of the absorption transition, or otherwise, it will cause the annealing temperature at the substrate. However, there will be-the minimum actual energy is lower than the desired annealing temperature range of 15 and cannot be reliably obtained. In the specific embodiment, the energy of the pre-heated light 150 is set higher than necessary to ensure that the annealing light is efficiently absorbed by the substrate, and a large range of annealing temperature is easily obtained. In a specific example, the preheating control requires :: the energy Pl that maintains the annealing state, that is, the maximum substrate temperature required to generate a 5th order of 20W, assuming a release time in release, as shown in the graph in FIG. 5 It indicates that the incident energy corresponds to about a face / cm. However, obtaining an intensity of _Cm in the preheated light beam to produce an image 160 with a width and annealed light beam image 30 is not as easy as its first appearance. In one embodiment, the laser light 15G is preferably cut to have a human beam ^ 21 200529327 at or near Brewster's angle, which is about 75. . This angle reduces reflected radiation and makes the energy absorbed by the type of structure that is to appear on the substrate uniform. At about 75. , The preheated radiant light 150 is wiped through the substrate 12 and the coverage area is increased four times and the intensity is reduced proportionally. 5 The total energy in the preheating radiant light 150 can be increased, for example, by adding additional laser diode columns to make the preheating source larger. However, this proportionally increases the width of the preheated radiant light 150. Increasing the width of the preheating radiation will increase the dwell time and the depth of thermal diffusion, which will further increase the energy required to obtain a given maximum temperature. Therefore, the replacement lens 143 needs to be designed so that it can provide a preheating radiation light 150 with a sufficient intensity, and the available preheating radiation source 142 is used to heat the substrate to within the critical temperature range. An embodiment of an alternative lens according to the present invention will be described below. 8A and 8B are sectional views of specific examples of the implementation of the optical replacement system 140 and the substrate 10, respectively. Figure 8A is a diagram on the Υ-Z plane, and Figure 8B is a diagram on the XY-Z plane. In Figures 8A and 8B, the replacement lens is divided into two parts to fit the layout, and the lens elements with surfaces S13 and S14 are shown in both parts. In this embodiment, the preheating radiation source 142 includes a 2-dimensional laser diode 20 array, such as a LightStack ™ 7xl / LPV array by Coherent Semiconductor Group. 5100 Patrick Henry Drive, Santa Clara, CA95054. The LightStackTN ^ column contains 7 water-cooled laser diodes each 10 mm long and 1.9 mm away from each other. Each diode column can emit 80 watts of optical energy. The replacement lens 143 includes an object plane OP (in which preheating 22 200529327 Tian radiation source 142 is configured) '-an image plane 1? (In which a substrate ⑼ is arranged, and an optical axis A2 connecting the image and the object plane. In Beiyuan For the specific example and the above, the replacement lens 143 is designed to generate a preheating radiation of 5 light 150 that forms an image 60 (such as a line image) and is scanned on the substrate 10. The scanning eye of the image 16 can be any number of This can be done using methods such as moving the chuck 28 (via the mobile stage MS) relative to the replacement lens 143 (fig. Ic). The substrate is irradiated with the image 16 area. The smaller image area is easier to heat the substrate to the required high beam intensity. Therefore, the preheating of the area provided by the replacement lens 143 must be synchronized with the irradiation of the substrate with the annealing radiation light 20. Because of the radiation of the laser diode The property is anisotropic and the difference between the adjacent diodes in the X and γ planes is large, and the replacement lens 143 needs to be deformed to efficiently form an image 16 on the substrate 10. In addition, in order to achieve an image 160 Required on the substrate 10 Intensity requires a relatively high numerical aperture on the image plane Ip. Therefore, referring to Figures 9A and 9B as well, the replacement lens 143 is composed of a preheating radiation source 142 and includes one with and as a preheating in order along the optical axis A2. Cylindrical lens array 200 of the same number of lenses 201 as the laser diode rows 198 of the radiation source 142. The cylindrical lens array 200 has energy in the γ_χ_ζ plane and is used to collimate the radiation from 20 preheating radiation sources 142 in the X-Z plane. Preheat the radiated light 147 (Figure 9A) 'so that the round shot has a cone angle of 10 ° in the X-Z plane (Figure 9B). The combination of the diode array and the cylindrical lens array is input to the deformation The replacement lens develops the cylindrical lens array onto the substrate. Table 1 lists the lens design data of the specific example 23 200529327 of the replacement lens 143 as illustrated in Figs. 8A and 8. Refer to Figs. 8A and 8B again. The replacement lens 143 is composed of two image replacement lenses R-1 and R-2 connected in series with the general intermediate image plane IM. The replacement lens R-1 is mainly used in the YZ and XZ planes and is completely different. The deformation of the circle of energy 5 cylindrical lens element replaces the lens, and The secondary replacement lens R-2 is a conventional replacement lens using a spherical element and having a 1: 6 zoom ratio. The anamorphic replacement lens R-1 has a 1: 1 zoom ratio on the YZ plane and on the XZ plane It has a 1:10 zoom ratio. The replacement lens 143 is telecentric in the object plane OP and the image focusing plane OP. 10 A spherical field lens 202 (surface sl-s2) and a cylindrical lens 204 are arranged next to the preheating radiation source 142. (Surface s3-s4), it can be reached that the object plane OP and the image plane IP are telecentric. The cylindrical lens 204 has energy only in the YZ plane, and forms an optical image at s5 of the YZ plane. Next, two cylindrical lenses 206 and 208 (surfaces s6-s9) having energy in the Y-Z plane are re-developed at a 1: 1 ratio of the 15-diode array on the intermediate image plane. The surface slO distinguishes the image of light in the X-Z plane. Then a pair of cylindrical lenses 210 and 212 (surfaces sll-sl4) having energy in the X-Z plane are used to develop the diode array in the middle image plane at a 10: 1 zoom ratio. This intermediate image is formed by a group of spherical lenses 214-222 (surfaces sl5-s24), which are secondary lenses, and are developed on the final image 20 image plane with a 6: 1 zoom ratio. Therefore, the replacement lens has a total zoom ratio of 6: 1 in a plane containing a diode column, and a zoom ratio of 60: 1 in a plane perpendicular to each diode column. The 6: 1 zoom ratio in the Y-Z plane reduces uncollimated light (slow axis) of 10mm in size to preheat the light source 142, from 10mm in the object plane OP to 1.61 mm in the image plane 24 200529327 plane IP. Similarly, the radiation radiated by the preheated light source μ] on the same plane is on the object plane OPIO. In the image plane, Ip increases to 60. . The zoom ratio in the X-Z plane is 60: 1. Therefore, a laser diode with a size of 11 · 4πιm (as measured across 7 rows of diodes in 5 directions), the effective radiation source 220 at the object plane OP is reduced to 0.19 mm in the image plane IP. In addition, the collimated light is in the effective radiation source 200. When the FWHM angle is scattered, Ip will be increased to 60 in the image plane. Cone angle. If it is assumed that the preheat radiation 10 I47 generated by the radiation source 142 in the object plane OP to the substrate in the image plane is 50% (including the reflection loss on the substrate surface 12), the effective transmission is 50%, then Figures 8A and 8B The alternate lens 143 can bring 280W to image 160. For an image 160 embodiment of a size of 1.6 mm by 0.19 mm, this can achieve an energy density of 921 W / mm2. At normal incidence (θ) 5 0 = 0, this energy density, assuming a dwell time of 0.2 ms, will increase by 15 room temperature (ie, ~ 20 ° C) from the temperature of the silicon substrate 10 to approximately 500 ° c to approximately 520 ° c. This will exceed the critical, uniform temperature Tc of 400 ° C required to start the self-sustained annealing state, and within a non-uniform temperature distribution range in front of the annealed laser image 30 generated by, for example, a diode array image 160. In this case, it is assumed that the preheating radiant light 150 is before the annealing radiant light 20 (ie, sweeping the surface before it). By this method, the preheating radiant light 20 can reach the preheating portion before the same preheating portion of the substrate is irradiated. The maximum temperature TMAX generated by thermal radiation. In an embodiment, the relative positions of the preheating and annealing radiation light are reversed each time the scanning direction is reversed, so that the preheating radiation light is always before the annealing radiation light. 25 200529327 IX · Xingchang light-scanning cat and its orientation As described above, in one embodiment, the image 160 formed by the preheating radiation light ΐ50 scans the substrate 10. At the same time, the image 30 formed by the addition of annealing radiation light also scans the substrate, making it incident on the area preheated by the preheated light.

In one embodiment, the scanning is performed by moving the substrate in a spiral, grid, or zigzag pattern. In a one-line scanning pattern, the scanning direction is reversed and the dual scanning position is increased after each scanning. In this case, as mentioned above, the relative positions of the preheating radiation light 15 and the annealing radiation light 20 need to be changed between each scan. In one embodiment, this can be achieved by moving the entire stomach replacement lens 143. When the annealing radiation light 20 is about ΐ20 μm wide (FWHM) and the preheating radiation light 250 is about 190 μm wide (flat curve), the replacement lens 14 3 needs to be moved about twice the distance between the centers of the two lights, or parallel to the scan. The direction of the eyelet direction is about 393 μηι. This can be accomplished by a signal such as the controller 32, which is operatively connected to the preheating replacement lens 143 to complete the movement of the replacement lens (FIG. 1C). In a similar method, the controller 32 controls the focus of the preheated radiant light 150 by adjusting the focus, tip and tilt parameters of the substrate before scanning the seedlings. As described in the aforementioned U.S. Patent Application Serial No. 10 / 287,864 20, the 'annealed radiant light 20 is incident on the substrate 10 at an incidence angle at or near Brewster's angle, and is preferably p-polarized. This is because the stacked films encountered on the substrate during annealing have a low reflectance and, in these cases, small reflectance differences. In the embodiment, the preheated radiant light 150 is configured to resemble 26 200529327 The fire field light 20 irradiates the substrate at an angle of incidence θ15 of or near the Brewster's angle. Generally, this angle reduces the reflectivity between different stacked films that can be seen on the substrate before the activation (annealing) step. However, although this light orientation (angle) works well at the annealing wavelength, it is not as effective at the wavelength used to preheat. The wavelength of the preheated radiation is approximately the same as the thickness of the thin film used to fabricate semiconductor structures (such as element 14, such as transistors), which can cause large differences in substrate reflectance at all angles of incidence. In addition, an angle of incidence θ150 at or near Brewster's angle will expand the image 160 to a region 3 to 4 times larger than the normal incidence (that is, θ150 =: 〇〇;) and reduce the energy density by a relative amount. If the rate of the eye-catching seedlings 10 is kept constant, since it is usually set by the annealing radiation structure, the maximum temperature is also reduced. One problem that arises when operating at or near normal incidence is that the light reflection will have a high reflection ratio, and if it returns to a radiation source (such as a diode array) it will cause severe damage. Figures 10A and 10B are diagrams illustrating an embodiment of a preheating optical replacement system 140 used to reduce the amount of preheating radiation 15 reflected, or scattered back to the preheating radiation source 142 (Figure 1C). By referring to FIG. 10A, in a preferred embodiment, the preheated radiant light 150 has a normal incidence angle of θΐ50 = 0 °. The vertical angle of incidence will cause a portion of the preheated radiation to be reflected by the substrate (the reflected preheated radiation is marked with 150R) and transmitted back to the preheated radiation source 20 142, which will accelerate the time of the source destruction . In an embodiment, when the preheating radiation 147 is polarized (such as in the case of a laser diode), the reflected preheating radiation light 150R returned to the preheating radiation source can be configured in the preheating radiation The polarization plate 143P aligned with the polarization direction of the light and the quarter wave plate i43WP located between the polarization plate and the substrate are reduced. The quarter-wave plate will transform the radiation from the 27 200529327 polarizer to the substrate into circularly polarized radiation on the substrate. Any radiation returned by the substrate is converted back to linearly etched polarized radiation after passing through the quarter wave plate. However, the direction of polarization of the return radiation is orthogonal. Therefore, the chirped return light does not pass through the polarizer and does not reach the laser diode array. 5 Now refer to FIG. 10] B. Even if you choose to deviate from normal incidence and θΐ50, the reflected (reflected) preheated radiation light 15 cannot return to the preheated radiation source 'and scatter back to the preheated radiation source. (Or non-reflective) preheating radiant light i50s can cause a problem. Even a small amount of radiation returned to some preheated radiation source types (such as lasers) can cause operational instability. Similarly, when deviating from the vertical 10-radiation operation, it is preferable to use p-polarized preheated radiation to increase the proportion of radiation absorbed on the substrate and reduce the difference in absorption due to different structures of the substrate. Therefore, in an embodiment, the preheating radiation 150S returned to the preheating radiation source 142 is reduced by adding a polarizer 143p and a Faraday rotator 143F at the rear section of the replacement lens M3. The Faraday rotator 143F is located between the polarized light 143P and the substrate 10. In operation, after passing through the rotator twice, the '泫 Faraday rotator 143F rotates the polarization of the preheated light 150 by 90. And the polarizing plate blocks the polarization preheating radiation light from returning to the preheating radiation source 142 for 15 seconds. By operating the optical replacement system 14o to deviate the preheated radiant light 15o from normal incidence, it also helps to measure the amount of energy of the reflected preheated radiant light 150R, which is helpful for analysis. Measuring the energy of the incident preheated radiant light 150 and the reflected preheated radiant light 150r can be used to calculate the energy absorbed by the substrate 10. This is then used to calculate the maximum temperature generated by the preheated radiant light 150. By fixing the energy absorbed by the preheating radiant light 150 above a minimum critical value, sufficient preheating can be ensured to stimulate the substrate to absorb strongly the radiant light 20. Although it is better to use the preheated light 150 to illuminate the substrate 10 at an angle of θ50 to minimize the reflection of the preheated radiation, this is not always convenient or possible. This is because the reflectivity of the substrate 10 is based on the nature of the surface 12 and may have various different films or other structures thereon. These structures include pure silicon, field oxides, and polycrystalline silicon on field oxides in the junction area. It has been calculated that a typical integrated circuit contains 30% to 50% field oxide, about 15% to 20% pure silicon or polycrystalline silicon on silicon, and the remainder is polycrystalline debris on% oxide. However, these properties are different in each circuit and even in one circuit. Figure π is a graph showing the reflectance difference R (%) versus the incident angle θ150 (degrees) of the pure silicon and field oxide thin film (300nm, 400nm, and 500nm) embodiments, which is typically shown when the silicon is ready to be bonded and activated On the substrate. Figure 丨 丨 assumes that the radiation incident on the substrate has a wavelength of 800 nm and is P-polarized. It can be seen from the figure that the optimal operating point for these films is equivalent to about 55. Angle of incidence, the reflectivity of all angles is approximately equal to 14%. Fig. 12 is a view similar to Fig. 11 and shows the reflectance of an oxide layer having a thickness of 300 nm, 400 nm, and 500 nm on a substrate having a thickness of i30 nm. There is no ideal operating angle of incidence in this case, however 55. For a reasonable 20 choice. In fact, the presence of activated dopants in polycrystalline silicon and silicon layers, k is used to make these areas more metal-like and to increase the reflectance at all angles of incidence. Simply refer to Figure 16 'which will be explained in more detail below, In order to transmit sufficient energy from the preheat radiation source 142 to the substrate 10, the preheat radiation light 丨 50 needs 29 200529327 to use a large range of incidence angles on the substrate, that is, the preheat lens 143 has a large numerical aperture ΝΑβιηφ ^ ο, where φ ^ ο is a half angle formed by the axis A2 and the preheated radiant light 150 outside the light beam 150 or 15 (^. Note that the angle of incidence θ) 50 is measured between the surface normal N and the axis A2, the latter in # It also represents the beam axis of the preheated light 1550. The angle range between the beam axis and the surface normal is the angle range of the "center angle". In an embodiment, if the The rounded corners of the range are inferred in FIG. 11 as a good choice to reduce the difference in reflectivity between various stacked films, and the range of the incident angle θΐM is from about 42. To about 10 62 °, with a median value of about 52 °. Since it is not easy to remove the preheating radiation reflected by the substrate, one embodiment of the present invention is related to capturing the reflected preheating radiation light 15R and guiding it back to the substrate as "circulating radiation light 150RD". It can be absorbed and used to heat the substrate. 15 Therefore, reference is now made to FIG. 13, which shows an enlarged schematic diagram of a specific embodiment of an LTA device 8 of the present invention, similar to FIG. 10B, which includes a configuration to obtain preheated radiant light 150 and reflected preheated radiant light. 150r, and guide it back to the substrate as a cyclic radiant light system 300 with cyclic radiant light 150RD. The circular light system 300 is arranged along the axis A3 to generate an angle θ] 50 relative to the surface normal. 20 In order to obtain optimal reflected preheated radiant light 150R for the cyclic radiation light system 300, in an embodiment, the angle 015ORD is made equal to the preheated radiant light incident angle θ15. FIG. 14 is a cross-sectional view of a specific example of a cyclic radiation light system 300, which includes a hollow right-angle reflector 310 and a collecting / focusing lens 316 having a focal length F consistent with the distance from the lens to the substrate surface 12 30 200529327. The hollow right-angle reflector 310 has three perpendicularly intersecting reflective surfaces. To simplify the illustration, only two surfaces 312 and 314 are shown in FIG. 14. During operation, the lens 316 collects the reflected and preheated light 150R 'from the substrate surface 12 and guides it to the right-angle mirror surfaces 312 and 314 as parallel light 320. This parallel light is reflected by the surface of the 3-mirror and is directed back to the opposite direction to the lens 316 as the parallel light 320, which now constitutes a cyclic preheating radiation light 150RD. The collimated light 320 'is collected by the lens 316 and refocused on the original point on the substrate surface 12. 10 15 20 FIG. 15 is a cross-sectional view showing a modified example of the embodiment in FIG. 14, in which the right-angle mirror 310 is expanded (deviated) from the axis A3 by an amount of AD. This results in a D-shaped human jacket on the substrate that is between the reflected preheating radiation light 150R & cycle preheating radiation light suit. Note that the position of the light in pure is still the same-only the angle of incidence changes. The angle of incidence between the two lights can be used: deviation to prevent the reflected person from shooting back to the __ source 142 and the instability of the radiation source. In this particular implementation example, the use of eight internal inverse orthographic refractions has no effect, because it cannot be implemented by the light = team Zhu / focus lens 450, and the grating bias of the right grating surface 462. Example of a sectional view. In the ―second concrete‖, the detail is the height of the first and second touches 472, the telecentric replacement lens, and a light stop 474 located between the first and second lenses. In addition, in this implementation, in the version, the lens has a length F1 on the substrate side and a focal focus on the grating side,… F2, and these lenses are configured so that 31 200529327 the substrate surface 12 is located away from the lens 470 along the axis A3. The distance F1 is measured, and the grating 460 is located away from the lens 472 and measures the distance F2 along the axis A3. The two lenses 470 and 472 are also separated to the same distance as the sum of their two focal lengths. The grating surface 462 is preferably suitable for optimizing the wavelength of the diffracted preheated radiant light 5 to 50, and to limit the incidence of the radiated light on the grating surface to be diffracted to return along the incident path. The optimal grating period P is P = nX / 2sincpG, where λ is the wavelength of the preheated radiation light '(Pg is the angle of the grating with respect to the grating surface normal ng, and η is the refractive index of the medium surrounding the grating (for Air time η = 1). The purpose of the grating 10 is to compensate the tilted focus plane on the substrate. On the other hand, according to the amount of the axial plane distance between the image point 468 and the replacement lens 450 in Figure 16 will cause the return The image is out of focus. Note that in this structure, the replacement lens 45 is operated at -ΐχ, 9G = cpi4B = cp23R = cp23RD. Generally tancpG = Mtancp23R, where M is the magnification from the substrate to the grating replacement lens 450. 15 Operation The reflected radiated light 150R is collected using a telecentric replacement lens 450, which includes a lens 470 and a lens 472, which bring the radiated light to a focal point on the grating surface 462. The grating surface 462 changes direction (or more precisely, The radiation light returns to the replacement lens 450, which guides the current circulating preheating radiation light 15RD back to the substrate surface 12 at or near the point 468, which is where the reflected radiation 20 light is generated. The specific example in FIG. 16 Disadvantage is reflected warm-up The radiated light 1511 forms a small image on the grating, which may cause the grating to eventually melt or be damaged in a continuous principle. Using a vertical incidence mirror (not shown) to replace the grating will encounter similar problems. Therefore, 'in the use of Figure 16 In the implementation of the specific example, 32 200529327 should be carefully operated as the device 8. Fig. 17 is a schematic cross-sectional view of a specific example of the embodiment for preheating the substrate 10, in which the device has a preheat radiation source 142 and 142 ', respectively. The two pre-heating optical replacement systems 140 and 140 ', and respectively emit pre-heating radiation light 5 150 and 150', which respectively form images 160 and 160 'on the substrate. In one embodiment, the pre-heating systems 140 and 140' 140 'is configured so that each of them forms at least partially overlapping images 160 and 160' on the substrate. This configuration reduces the high-energy preheat radiation light 147 and 147 'required by the preheat radiation sources 142 and 142'. In one embodiment, the preheat radiation sources 142 and 142 'are each a laser 10 diode array. In this embodiment, the laser diode array emits radiation with a wavelength of 780nm-840nm. Heat radiation Sources 142 and 142 'are operatively connected to controller 32. In an embodiment, the annealing radiation 20 (Figure 1C) is at or near the Brewster's angle of silicon (that is, at 10.6 μm) Θ2〇 ～ 75。) Enter 15 to the substrate surface 12. The preheated radiant light 150 and 150 in Figure 17 are incident at θ15〇 and Θ15θ, which will be different from Brewster's angle, because the preheated light is more The big horns are scattered. In one embodiment, the incidence angles ㊀% and θ50 are equal (for example, about 52 °), and in another embodiment, the incidence angles 6150 and 015 () are different. 20 In an embodiment, the images 160 and 160 are formed before the image 30 (that is, at the front end of the scanning direction), so that when the light is scanned relative to the substrate surface, the substrate reaches the annealed light 20 (which is accompanied by Image 30) Preheating before irradiating the preheating area of the substrate. The specific example of FIG. 17 is not limited to the two preheating radiant lights 150 and 33 200529327 UO '. In general, any reasonable number of sides form a relative image. The "," and upward light can be used to achieve the desired preheating effect on the substrate surface. In the above detailed description, it is specifically explained for the sake of detailed explanation. Therefore, its It means that the additional towels should cover all the features and advantages of the device following the true spirit and norms of the present invention. In addition, since those skilled in this art will quickly think of several improvements and changes, there is no need to limit this. The actual structure of the invention is made in this system. According to Table 1 · As shown in Figures 8A and 8B, the replacement lens 143 is an embodiment of the lens >; the design value b and the radius (RDY, RDX) ΤΗ Glass ΝΒΚ7 element lens 202 1 2 RDY = RDX = 8 RDY = RDX = -142.696 3.100 0.500 3 RDY = RDX = 8 5.800 ΝΒΚ7 lens 204 4 RDY = -30.060 RDX = 8 107.027 6 RDY = 544.836 RDX = 8 7.800 Β270 lens 206 7 RDY = -47.730 RDX = 8 113.564 8 RDY = 99.955 RDX = 8 8.00 ΝΒΚ7 lens 208 9 RDY = 1309.204 RDX = 8 52.015 11 RDY = 8 RDX = 38.835 9.900 ΝΒΚ7 lens 210 12 RDY = RDX = 8 6.946 13 RDY = 8 RDX = -199277.3 9.600 ΝΒΚ7 lens 212 14 RD Y = 8 RDX = -13.079 338.951 15 RDY = RDX = 50.084 6.749 ΝΒΚ7 lens 214 16 RDY = RDX = 693.301 19.454 17 RDY = RDX = 21573827 3.000 ΝΒΚ7 lens 216 18 RDY = RDX = 34.369 5.895 19 RDY = RDX = 946.3332 9.000 ΝΒΚ7 Lens 218 20 RDY = RDX = -84.838 .500 21 RDY = RDX = 46.343 6.370 Fused silica lens 220 22 RDY = RDX = 22.240 42.168 23 RDY = RDX = 4434.483 8.000 Fused silica lens 222 24 RDY = RDX = 8 Image plane 21.000 34 200529327 Brief description] Figure 1A is a cross-sectional view of a specific embodiment of the LTA device of the present invention, which includes the LTA optical system and the silicon substrate processed by the system. The LTA device includes a heated clamp The substrate to support and preheat the substrate, and an optional thermal barrier surrounding the chuck to reduce radiation transmission to the remaining devices and promote substrate heating efficiency; Figure 1B is a device similar to Figure 1A of the present invention. A cross-sectional view of the specific embodiment includes a heating kit for preheating the substrate around the substrate; FIG. 1c is a top view of the embodiment 2 of the device according to the present invention similar to FIG. 1A Should be added The hot chuck and optional insulation barrier are replaced by a light pre-heating system, which is suitable for preheating at least a part of the substrate with preheating radiant light; i 15 Figure 2 is an annealing radiation called ^ skin length A graph of the absorption length la_) of the doped silicon substrate 15 against the substrate temperature Ts (t :), and a graph of the diffusion length LD (pm) at the 200-dwell time versus the substrate temperature Ts (° c); Figure 3 is a computer simulation of the substrate temperature as a function of depth (μηι) and annealing radiation position (_ as a function of the curve, showing the "hot spots" formed on the substrate by annealing dimming and self-sustaining annealing-like evil; 20 Figure 4A is A schematic diagram shows the relative intensity and light curve of the preheated and annealed light rays as a function of the position on the substrate surface in an embodiment. Figure 4B is an enlarged cross-sectional view of the substrate. How does the hot light radiate the heat of the substrate, how to promote the substrate to self-maintain the annealing state of the light from the annealing light; 35 200529327 Figure 5 shows the maximum substrate temperature TMAX (t) produced by the substrate with an annealing wavelength of 10. The incidence of the light emitted by the annealing Figure of energy P (W / cm); Figure 6 is a diagram of the initial temperature of an undoped substrate with the highest substrate temperature (5 TMAxrc) 'obtained from two-dimensional finite element simulation on the un-doped substrate. ; Figure 7 is a diagram of the absorption length of preheated radiated light at 780nm ^ (handsome) vs. substrate temperature TS (° C); Figure 8A is a cross-sectional view of a specific example of the optical replacement system of Figure 1C, 10 is at Figures on the YZ plane; ', Figure 8B is a sectional view of a specific example of the optical replacement system of Figures 1C and 8A, which is a diagram on the XZ plane; Figure 9A is a heating light source and a cylindrical lens Enlarged sectional view of the array on the plane; 15 Figure 9B is an enlarged sectional view of the heating radiation source and the cylindrical lens array in the γ_ζ plane; Figure 10A is a preheating radiation source, which replaces the lens and the preheated Kota light that is perpendicular to the substrate. The enlarged schematic diagram further includes a polarizing plate and a quarter-wave plate configured to reduce the amount of preheat radiation 20 reflected by the substrate and returned to the preheat radiation source by the preheat radiation light; FIG. 10B is Preheating radiation source, replacement lens and normal incidence substrate The large diagram also includes a polarizer and a Faraday rotator arranged in the preheat radiation to reduce the amount of preheat radiation scattered by the substrate and returned to the preheat radiation source; 36 200529327 Figure 11 shows the reflection Rate difference R (%) is a graph of the incident angle of 150 (degrees) for pure silicon and field oxide film thicknesses of 300 nm, 400 nm, and 50 nm on a silicon substrate. Figure 12 is similar to Figure 11 'Xinbu 1 thick layer of polycrystalline seconds and 5 have a thickness of 30nm, 400nm and 500nm on the substrate < reflectance of the oxide layer; Figure 13 is a specific example of the implementation of the LTA device similar to Figure 10B of the present invention The fa image is enlarged, but it includes a circular optical system 300 configured to obtain a reflection preheat light beam 150R and guide it back to the substrate; 0 Figure M is the specific implementation of the circular radiation light system of Figure 13 A cross-sectional view of the example includes a right-angle mirror and a collecting / focusing lens; FIG. 15 is a cross-sectional view showing a modification of the specific example in FIG. 14, where the right-angle mirror is expanded (deviation) relative to the axis A3 by △ 〇 amount, resulting in direct incident and cyclic preheating radiation The incident angle deviates from each other. 5 FIG. 16 is a cross-sectional view of another embodiment of the cyclic optical system in FIG. 13, which includes a collecting / focusing lens and a grating; FIG. 17 is a substrate for preheating the substrate. A schematic cross-sectional view of the configuration of the specific embodiment of the embodiment, which uses two preheating optical replacement systems with similar incidence angles at both ends of the substrate normal. 37 200529327 Symbol description of main components] 8 ··· device 10 ... substrate 12 ... substrate surface 16 ... body area 18 ... continuous annealing radiation 20 ... continuous annealing radiation 20R ... reflected radiation 20 '... absorbed annealing radiation 22 ... Arrow 22 '... Arrow 25 ... LTA optical system 26 ... Annealed radiation source 27 ... LTA lens 28 ... Chuck 29 ... Stage driver 30 ... Image 31 ... Hot spot 32 ... Controller 50 ... Heating element 52 ... Power supply 53 ... Thermal insulation Layer 56 ... heat 57 ... temperature sensor 62 ... thermal barrier 64 ... aperture 80 ... heating kit 82 ... interior space 84 ... window or aperture 140 ... optical replacement system 140 '... optical replacement system 142 ··· Preheating radiation source 142 '... Preheating radiation source 143 ... · Replacement lens 143P ... Polarizer 143WP ... Quarter wave plate 143F ... Faraday rotator 147 ... Radiation light 150 ... Preheat radiation 150 '... preheat radiation 150R ... reflected preheat radiation 150S ... preheat radiation 150RD ... cyclic radiation 160 ... image 160' ... image 166 ... thermal 198 ... laser diode array 38 200529327

200 ... cylindrical lens array 201 ... lens 202 ... spherical field lens 204 ... cylindrical lens 206 ... cylindrical lens 208 ... cylindrical lens 210 ... cylindrical lens 212 ... cylindrical lens 214-222 ... spherical Lens 250 ... Preheat radiation 300 ... Cyclic radiation system 310 ... Hollow right-angle mirror 312 ... Right-angle mirror surface 314 ... Right-angle mirror surface 316 ... Collecting / focusing lens 320 .... Parallel light 320 '... Parallel light beam 450 ... Collection / focusing lens 460 ... Thumb 462 ... Thumb surface 468 ... Image point 470 ... First lens 472 ... Second lens 474 ... Aperture Light block

39

Claims (1)

200529327 X. Scope of patent application: 1. A device for preheating a substrate with a surface, which uses laser annealing annealing light that is not absorbed by the substrate at room temperature to perform laser thermal annealing on the substrate. The device includes: 5 a preheating radiation source suitable for emitting a large amount of preheating radiation absorbed by the substrate at room temperature; a suitable source for obtaining the preheating radiation and forming a preheating radiation light, and forming a first image on the substrate A replacement lens, in which the first image scans the surface of the substrate to preheat the area of the substrate in front of or partially overlapping the second image 10 formed by the annealed radiation light; and a configuration to obtain the preheat reflected by the substrate Radiate and guide the reflected preheated radiation back to the substrate as a cyclic optical system of cyclic radiant light. 2. The device according to item 1 of the patent application scope, wherein the circulating optical system 15 includes a collecting / focusing lens and a corner reflector. 3. The device according to item 2 of the patent application, wherein the circulating radiation light and the preheating radiation light each have an incident angle, the circulating optical system has an optical axis, and wherein the right-angle mirror is moved relative to the optical axis To at least partially separate the circulation and the pre-heated light incident angles. 20 4. The device according to item 1 of the patent application scope, wherein the circulating optical system includes a telecentric replacement lens and a diffractive light thumb. 5. —A device for preheating a substrate with a surface, using annealing annealing light that is not largely absorbed by the substrate at room temperature to perform laser thermal annealing on the substrate. The device contains: 40 200529327 various configurations to use First and second preheating optical systems each having first and second preheating radiant wavelengths that are largely absorbed by the substrate at room temperature; and a first and second scan The first and second 5 preheating radiation lights generated by the image are held in front of the third scanning image generated by the annealing radiation light during the preheating radiation light and the annealing radiation light are scanned with respect to the substrate. 6. The device according to item 5 of the patent application, wherein the first and second preheated radiations are P-polarized and incident on the substrate surface at an angle that reduces the difference in structural absorption existing on the substrate. 7. The device as claimed in claim 5, wherein the first and second preheated radiated light have equal but opposite incident angles. 8. A device for preheating a substrate with a surface, using annealing radiation that is not substantially absorbed by the substrate at room temperature to perform laser 15 thermal annealing on the substrate, the device includes: several preheating optics Each system is configured to irradiate a portion of the substrate with a plurality of preheating radiation lights having a wavelength that is largely absorbed by the substrate at room temperature; and the plurality of preheating radiation lights respectively form an image, and when the preheating radiation 20 light and the The annealing radiation is held in front of an annealing radiation image when the substrate is scanned. 9. A method for preheating the surface of a substrate, using laser annealing to anneal the substrate with annealed radiation that is not substantially absorbed by the substrate at room temperature, the method comprising: 41 200529327 irradiating the substrate with a preheat radiation A portion; obtaining the preheated radiant light reflected by the substrate portion; and directing the obtained radiation back to the substrate portion. 10. The method according to item 9 of the patent application, wherein directing the obtained radiation 5 back to the substrate includes reflecting the obtained radiation using a corner reflector. 11. The method according to item 9 of the patent application, wherein directing the obtained radiation back to the substrate portion includes reflecting light shots obtained by a roof mirror and a cylindrical mirror. 10 12. The method according to item 9 of the scope of patent application, wherein directing the obtained radiation back to the substrate portion includes diffracting the obtained radiation using a diffraction grating, which is inclined relative to the obtained radiation so that the radiation is Guide back to the substrate and keep focus on the substrate surface. 13. —A method for preheating a substrate with one surface, using a thermal annealing annealing light that is not absorbed by the substrate at room temperature 15 to a large extent, the method includes: The first and second preheated radiations of wavelengths that are largely absorbed by the substrate at temperature illuminate the first portion of the substrate; and when the preheated radiation and the annealing radiation are scanned relative to the substrate surface 20, the first One part is in front of the second part of the surface of the substrate illuminated by an annealing radiation, so that when the annealing radiation encounters the heated first part, it will be absorbed by the substrate in a large amount. 14. The method according to item 13 of the patent application, wherein the first and second preheating radiation lights have the same wavelength. 42 200529327 15. The method according to item 13 of the patent application, wherein the annealing radiation is incident on the substrate at Brewster's angle, and wherein each preheating radiation is incident on the substrate within an angle range including a central angle, wherein each angle range The center angle is different from Brewster's angle. 5 16. The method according to item 13 of the patent application, wherein the annealing radiation light and the preheating radiation light are incident at angles at which the difference in absorbance of structures existing on the substrate is reduced. 17. The method according to item 13 of the patent application scope, comprising forming the first and second preheated radiant light, each of which has i) a numerical aperture between 0.15 and 0.5 on the substrate and ii) about 52 ° The angle of incidence. 43