CN107557871B - Laser annealing apparatus and method - Google Patents

Abstract

The present invention provides a laser annealing device and method. The annealing device includes: the laser light source subsystem, which is controlled by the host to generate and output laser light; the temperature monitoring subsystem, which monitors the laser irradiation on the silicon wafer surface The temperature at the position is fed back to the host; the optical subsystem is controlled by the host to shape and transmit the laser output from the laser light source subsystem to obtain a light spot with uniform distribution of light intensity; the space The light intensity modulation subsystem is controlled by the host to modulate the laser emitted by the optical subsystem, so that the light intensity distribution of the light spot incident on the surface of the silicon wafer corresponds to the reflectivity of the silicon wafer surface, Thus, the absorbed energy at each light spot position on the surface of the silicon wafer is consistent, and the energy can be determined according to the monitored temperature; the host computer controls the laser light source subsystem and the optical subsystem according to the feedback from the temperature monitoring subsystem And space light intensity modulation subsystem.

Description

Laser annealing apparatus and method

technical field

The invention relates to the field of silicon wafer processing, in particular to an annealing device and method after silicon wafer photolithography.

Background technique

Driven by Moore's Law, the chip manufacturing industry has experienced rapid development in the past few decades. This continued rapid development stems from the continued shrinking of chip sizes. Correspondingly, this smaller size poses increasingly higher difficulties and challenges to the chip manufacturing process. Traditional rapid thermal annealing methods for silicon wafers have been difficult to meet the requirements of 45nm and higher nodes. New alternative annealing techniques are being intensively investigated.

Due to the development of laser application technology in recent years, laser annealing technology has shown good application prospects. Compared with traditional annealing, laser annealing has a small thermal budget and high activation efficiency, which can greatly reduce the thermal diffusion of dopant impurities and reduce thermal strain.

After the silicon wafer undergoes a photolithography process, different nanometer (nm)-level geometric structures and material properties will be formed at different positions on the surface, resulting in inconsistent absorption of incident laser energy at different positions on the surface, resulting in surface discoloration after laser annealing. The uniformity of the temperature distribution becomes worse, the so-called pattern effect.

As shown in FIG. 1 , it is a schematic diagram of the surface structure of a silicon wafer after being processed by a specific photolithography process. It can be seen that there are a series of bare chips shown in black boxes on the surface of the silicon wafer. For the formed bare chip, there are a series of specific spatial structures with a nanometer (nm)-level spatial scale on the surface, and different material compositions at the inner depth, as shown in FIG. 2 . Based on the above factors, according to electromagnetic wave theory, for incident light with a specific wavelength λ and incident angle θ, the reflectivity R _{θ at the surface of the silicon wafer, λ} (x, y) is a function of position, where (x, y) represents the Positional coordinates at the surface of the annealed silicon wafer.

During the laser annealing process, for the target silicon wafer mentioned above, the laser is used as an energy source to irradiate the surface of the silicon wafer to be treated, so that the silicon wafer reaches the specified annealing temperature T0, and the target annealing is realized. As mentioned above, since the reflectivity R _{θ, λ} (x, y) is a function of position, it leads to differences in the laser energy absorbed at each position, which further leads to a certain range of temperature distribution at different positions of the silicon wafer to be processed. △T, this temperature difference caused by the different reflectivity or absorptivity of the surface, is generally called "pattern effect".

The temperature non-uniformity caused by this pattern effect will produce different diffusion kinetics of dopant particles, which will ultimately have an important impact on the consistency of device performance in the silicon wafer. Therefore, it is an important issue to avoid the pattern effect and keep the temperature change ΔT within an acceptable range during the laser annealing process.

It should also be pointed out that:

Figure 1 is a schematic diagram of a silicon wafer with a distribution of bare chips after the photolithography process, where the circular part with a dot pattern represents the silicon chip; the rectangular part with a grid pattern represents the bare chip:

Figure 2 is a schematic diagram of the geometric structure and material properties of the bare chip. The upper left figure shows a single bare chip, and the upper right figure shows the periodic spatial distribution of the bare chip on the surface of the silicon wafer; the lower right shows four different The material properties, A means all-silicon material (Si), B means polysilicon (P-Si) grown on the silicon material, C means silicon dioxide (SiO2) grown on the silicon material, which is covered with polysilicon (P-Si) -Si), D indicates that the silicon material is grown on top of silicon dioxide (SiO2).

In the prior art, US2013/0196455A1 utilizes a long-wavelength CO ₂ laser to selectively target polarized light in a specific direction at the Brewster angle, so that the R _{BrewsterAngle at different positions, λ} (x, y) The variance is reduced, thereby mitigating pattern effects.

In this scheme, there are the following problems:

1. The pattern effect cannot be completely eliminated: on the one hand, when the polarized light in the orthogonal direction interacts with the surface of the silicon wafer to be processed, it will still be partially absorbed; on the other hand, the theoretical Brewster angle can only be infinite Approximate, and for a spot with a certain spatial distribution, it must have a certain distribution near the Brewster angle, so the incident light in the above-mentioned specific polarization direction also has a pattern effect;

2. Poor process adaptability and low degree of control freedom: For complex and changeable silicon wafer surface patterns, corresponding measures to eliminate pattern effects cannot be taken.

Contents of the invention

The technical problem to be solved by the present invention is how to effectively deal with the pattern effect.

In order to solve this technical problem, the present invention provides a laser annealing device, including a host, a laser light source subsystem, an optical subsystem, a spatial light intensity modulation subsystem, and a temperature monitoring subsystem,

The laser light source subsystem is controlled by the host to generate and output laser light;

The temperature monitoring subsystem monitors the temperature at the laser irradiation position on the surface of the silicon wafer and feeds it back to the host computer;

The optical subsystem is controlled by the host computer to shape and transmit the laser output from the laser light source subsystem to obtain light spots with uniform distribution of light intensity;

The spatial light intensity modulation subsystem is controlled by the host to modulate the laser light emitted by the optical subsystem, so that the light intensity distribution of the light spot incident on the surface of the silicon wafer is related to the reflectivity of the surface of the silicon wafer Correspondingly, so that the energy absorbed at each light spot position on the surface of the silicon wafer is consistent, and the energy can be determined according to the monitored temperature;

The host computer controls the laser light source subsystem, the optical subsystem and the spatial light intensity modulation subsystem according to the feedback from the temperature monitoring subsystem.

Optionally, the laser light source subsystem includes one or more lasers, and each laser is independently controlled by the host.

Optionally, the optical subsystem includes:

The light spot detection mechanism measures the energy and corresponding spot position of the laser output by the laser light source subsystem and feeds it back to the host;

The energy attenuation mechanism is controlled by the host, and controls the energy of the laser light output by the laser light source subsystem according to the measurement result of the spot detection mechanism;

The beam expander and collimation mechanism is controlled by the host to control the spot shape of the laser light controlled by the energy attenuation mechanism;

And a uniform light mechanism, which is controlled by the host to shape the laser spot whose shape is controlled, so as to obtain a uniform light spot.

Optionally, the spatial light intensity modulation subsystem includes a spatial light intensity modulator and a modulator loading platform for loading the spatial light intensity modulator, wherein:

The spatial light intensity modulator, controlled by the host, transmits or reflects the uniform light spot emitted by the optical subsystem to the surface of the silicon wafer.

Optionally, the light transmittance T _θ,λ (x,y) of the laser emitted by the spatial light intensity modulator is adapted to the reflectivity R _θ,λ (x,y) of the surface of the silicon wafer, Satisfy the following relationship:

Wherein, the light transmittance T _θ,λ (x,y) of the laser refers to the ratio of the laser emitted from the spatial light intensity modulator to the laser incident to the spatial light intensity modulator, and λ is the ratio of the incident light wavelength, θ is the incident angle of the incident light, and (x, y) represent the position coordinates at the surface of the silicon wafer.

Optionally, during annealing, both the spatial light intensity modulator and the silicon wafer are discretized into several spatial grid points, and the reflectance corresponding to the adjacent spatial grid points on the spatial light intensity modulator is selected according to the allowable value The maximum distance max(△x,△y) needs to satisfy:

Wherein, the Δx is the distance between the adjacent spatial grid points on the silicon wafer along the X direction, the Δy is the distance between the adjacent spatial grid points on the silicon wafer along the Y direction, and the is the characteristic thermal diffusion length, satisfying D is the thermal diffusivity, and τ is the exposure time experienced by a point on the surface of the silicon wafer.

Optionally, the host includes a laser light source control subsystem for controlling the laser light source subsystem, an optical control subsystem for controlling the optical subsystem, and a spatial light intensity modulation control subsystem for controlling the spatial light intensity modulation subsystem. system.

Optionally, the annealing device for improving annealing uniformity based on reflectivity distribution further includes a silicon wafer stage, the silicon wafer is loaded on the silicon wafer stage, and the silicon wafer is driven by the control of the host computer. The wafer is moved horizontally so that the light spot can spread across the surface of the silicon wafer.

Optionally, the silicon wafer stage is controlled by the host through a silicon wafer stage control subsystem.

Optionally, the silicon wafer stage can also be controlled by the host to drive the silicon wafer to move vertically, so as to meet the depth of focus requirement.

Optionally, the spatial light intensity modulation subsystem further includes a spatial light intensity modulation imaging unit, which reduces or enlarges the light spot modulated by the spatial light intensity modulator.

Optionally, the laser annealing device further includes a galvanometer scanning subsystem, which controls the movement of the light spot relative to the silicon wafer, so that the light spot can cover the surface of the silicon wafer.

The present invention also provides a laser annealing method, comprising the following steps:

Step 1, annealing the silicon wafer with the surface pattern with the annealing wavelength to be used and the incident angle of the laser incident on the surface of the silicon wafer, and measuring the reflectivity of the silicon wafer surface;

Step 2, making a spatial light intensity modulator, so that the light intensity distribution of the spot where the laser modulated by the spatial light modulator is incident on the surface of the silicon wafer corresponds to the reflectivity of the surface of the silicon wafer, so that the The energy absorbed at each light spot position on the surface of the silicon wafer is consistent;

Step 3, uploading a silicon wafer with the same surface pattern to the workpiece table;

Step 4, controlling the movement of the workpiece table, so that the light spot after passing through the spatial light intensity modulator spreads over the entire surface of the silicon wafer, and completes the annealing of the silicon wafer;

Step 5. Step 3 is repeated until the annealing of all silicon wafers with the same surface pattern is completed.

Optionally, the light transmittance T _θ,λ (x,y) of the laser emitted by the spatial light intensity modulator is adapted to the reflectivity R _θ,λ (x,y) of the surface of the silicon wafer, Satisfy the following relationship:

Wherein, the light transmittance T _θ,λ (x,y) of the laser refers to the ratio of the laser emitted from the spatial light intensity modulator to the laser incident to the spatial light intensity modulator, and λ is the ratio of the incident light wavelength, θ is the incident angle of the incident light, and (x, y) represent the position coordinates at the surface of the silicon wafer.

Optionally, during annealing, both the spatial light intensity modulator and the silicon wafer are discretized into several spatial grid points, and the reflectance corresponding to the adjacent spatial grid points on the spatial light intensity modulator is selected according to the allowable value The maximum distance max(△x,△y) needs to satisfy:

Wherein, the Δx is the distance between the adjacent spatial grid points on the silicon wafer along the X direction, the Δy is the distance between the adjacent spatial grid points on the silicon wafer along the Y direction, and the is the characteristic thermal diffusion length, satisfying D is the thermal diffusivity, and τ is the exposure time experienced by a point on the surface of the silicon wafer.

Optionally, the step 4 further includes controlling the spatial light modulator to move synchronously with the workpiece table so that the light spot after passing through the spatial light modulator covers the entire surface of the silicon wafer.

The present invention proposes a laser annealing device and a laser annealing method, the main content of which is based on the reflectivity distribution of the target silicon wafer to be annealed, using the corresponding spatial light intensity modulation subsystem to make the silicon wafer to be annealed absorb the The energy is uniform, thereby eliminating the pattern effect and ensuring the consistency of device performance.

Description of drawings

Fig. 1 is the schematic diagram of the silicon wafer after photolithography process in the prior art;

Fig. 2 is a schematic diagram of bare chip material and structure after photolithography process in the prior art;

3 is a schematic diagram of an annealing device based on reflectivity distribution to improve annealing uniformity in an optional embodiment of the present invention;

Figure 4 is a schematic diagram of an optical subsystem in an alternative embodiment of the present invention;

Figure 5(a) is a schematic diagram of the spatial light intensity modulation subsystem in an optional embodiment of the present invention;

Fig. 5(b) is a characteristic schematic diagram of the spatial light intensity modulator in an optional embodiment of the present invention;

Fig. 6 is a schematic diagram of the variation of temperature with the distance from the heat source in an alternative embodiment of the present invention.

Detailed ways

The annealing device for improving annealing uniformity based on the reflectance distribution provided by the present invention will be described in detail below in conjunction with FIGS. 1 to 6. It is an optional embodiment of the present invention. It can be modified and polished within the scope of spirit and content.

The present invention provides an annealing device for improving annealing uniformity based on reflectivity distribution, including a host 000, a laser light source subsystem 100, an optical subsystem 200, a spatial light intensity modulation subsystem 300, and a temperature monitoring subsystem 400, wherein:

The temperature monitoring subsystem 400 monitors the temperature at the laser irradiation position on the surface of the silicon wafer and feeds it back to the host; in other words, it monitors the temperature of the laser irradiation area (Spot) on the surface of the silicon wafer (Wafer) to be processed in real time; further specifically Said to be composed of a pyrometer or a reflectivity detector, real-time measurement of the temperature of the upper surface of the silicon wafer at the position of the light spot can be realized. The temperature signal is measured in real time and fed back to the host 000 as the basis for feedback control.

The laser light source subsystem 100 is controlled by the host 000 to generate and output laser light; it can be understood as being used to generate and control laser light. The laser light source subsystem 100 includes one or more lasers, and each laser is independently controlled by the host. At the same time, according to the control signal provided by the host 000, the power/energy and wavelength of the laser output by each laser can be independently regulated through the laser light source control subsystem C100. In an optional embodiment of the present invention, the energy/power of the laser is adjustable.

The optical subsystem 200 is controlled by the host 000 to shape and transmit the laser output from the laser light source subsystem 100 to obtain a spot with uniform light intensity; it is mainly used to shape and transport the light beam;

In an optional embodiment of the present invention, the optical subsystem 200 includes:

The spot detection mechanism 2001 measures the energy and the corresponding spot position of the laser output by the laser light source subsystem 100 and feeds it back to the host 000;

The energy attenuation mechanism 2002 is controlled by the host 000, and controls the energy of the laser light output by the laser light source subsystem 100 according to the measurement result of the spot detection mechanism 2001;

The beam expander and collimator mechanism 2003 controls the spot shape of the laser light controlled by the energy attenuation mechanism 2002 .

The beam expanding and collimating mechanism 2003 is controlled by the host 000 to control the shape of the laser spot;

The uniform light mechanism 2004 is controlled by the host computer 000 to shape the laser spot whose shape is controlled, so as to obtain a uniform spot.

Based on the above, each independent optical subsystem 200 includes: a spot detection system 2001, which is composed of energy detection devices such as a power meter and a CCD, and an image acquisition device. The relative position in the chip, these data are mutually input into the host computer (000), and fed back to the stage control system C400 to realize the annealing of the entire silicon chip; the energy attenuation system 2002 is composed of an attenuation plate or a wave plate plus a polarization beam splitter prism Composition, by changing the transmittance or polarization direction of the lens, real-time control of the energy incident on the surface of the silicon wafer (Wafer) is realized; the beam expander collimation system 2003 can be composed of a single lens or a telescope system to realize the real-time control of the energy incident on the wafer surface The shape of the spot (Spot) on the surface of the silicon wafer is controlled; the uniform light system 2004 can be composed of a microlens array or an integrating rod, so that the spot after shaping has a specific light intensity distribution. Traditionally, the light spot after passing through the optical subsystem generally has a linear uniform distribution of light intensity and a high aspect ratio, that is, it is narrow in the scanning direction and long in the non-scanning direction.

The spatial light intensity modulation subsystem 300 is controlled by the host computer 000 to modulate the laser light emitted by the optical subsystem 200, so that the light intensity distribution of the light spot incident on the surface of the silicon wafer is consistent with that of the surface of the silicon wafer. Corresponding to the reflectivity, so that the energy absorbed at each light spot position on the surface of the silicon wafer is consistent, and the energy can be determined according to the monitored temperature;

Further, in an optional embodiment of the present invention, the spatial light intensity modulation subsystem 300 includes a spatial light intensity modulator 3001 and a modulator loading platform 3002, wherein:

The spatial light intensity modulator 3001 is controlled by the host 000, and transmits or reflects the uniform light spot emitted by the optical subsystem to the surface of the silicon wafer;

The modulator loading platform 3002 is loaded with the spatial light intensity modulator 3001 and is controlled by the host 000 to move.

When the uniform light spot shaped by the optical subsystem 200 is transmitted or reflected by the spatial light intensity modulator 3001 to the surface of the silicon wafer to be annealed, a spatially non-uniform light field distribution is formed; It moves synchronously with the modulator carrier stage 3002 of the spatial light intensity modulator 3001, so that the modulated non-uniform light spot spreads over the surface of the silicon wafer to be annealed, and the annealing process is completed.

FIG. 5( b ) shows a general schematic diagram of the spatial light intensity modulator 3001 . The picture on the left shows the change of light transmittance of the spatial light intensity modulator 3001 (indicated by the grayscale value); the picture on the right shows the general spatial layout and key dimensions of the spatial grid points.

In terms of function, the spatial light intensity modulator 3001 is located between the silicon wafer and the optical subsystem 200, the purpose of which is to form a uniform light spot on the surface of the silicon wafer through the change of the spatial light transmittance for the uniform light spot formed by the optical subsystem 200. The light intensity distribution spots corresponding to the reflectivity R _{θ and λ} (x, y) on the surface of the silicon wafer ensure that the energy absorbed at each position on the surface of the silicon wafer is consistent.

In other optional embodiments of the present invention, the spatial light intensity classification system 300 can also add a spatial light intensity imaging unit 3003 with a telecentric property and a certain magnification to reduce the modulated light spot Or zoom in, which is easy to manufacture the spatial light intensity modulator 3001 .

It can be seen that, in an optional embodiment of the present invention, the light transmittance T _θ,λ (x,y) of the laser emitted by the spatial light intensity modulator is related to the reflectivity R _θ,λ of the silicon wafer surface (x, y) fit, satisfy the following relationship:

Wherein, the light transmittance T _θ,λ (x,y) of the laser refers to the ratio of the laser light emitted from the spatial light intensity modulator 3001 to the laser light incident to the spatial light intensity modulator 3001, and λ is the incident The wavelength of the light, θ is the incident angle of the incident light, and (x, y) represent the position coordinates on the surface of the silicon wafer.

For the geometry and size, it mainly depends on the geometry and size of the silicon wafer to be annealed. Furthermore, because behind the spatial light intensity modulator, a zoom-in or zoom-out optical imaging system can be placed, but the upper surface and space of the silicon wafer must be guaranteed. The light intensity modulator surfaces have a one-to-one mapping relationship.

For the critical size of the spatial grid point of the spatial light intensity modulator 3001, it is defined as the allowable maximum distance of the reflectance of adjacent spatial grid points in the spatial light intensity modulator at the surface of the silicon wafer, that is, max(△x, Δy) needs to satisfy the following relationship:

Wherein, the Δx is the distance between the adjacent spatial grid points on the silicon wafer along the X direction, the Δy is the distance between the adjacent spatial grid points on the silicon wafer along the Y direction, and the is the characteristic thermal diffusion length, satisfying D is the thermal diffusivity, and τ is the exposure time experienced by a point on the surface of the silicon wafer. Theoretically, at the characteristic thermal diffusion length The temperature is considered to be uniform over a distance. As shown in Figure 6, in practical applications, under the action of a 300ns pulse, when the temperature is close to 1680K, the characteristic thermal diffusion length is about 2um, and within a distance of 0.2um, the temperature difference is less than 10K. Therefore, the spatial resolution after discretization must be guaranteed to be less than or equal to the distance of 0.1-1 characteristic thermal diffusion length.

In most optional embodiments of the present invention, the host computer controls the laser light source subsystem, the optical subsystem and the spatial light intensity modulation subsystem according to the feedback from the temperature monitoring subsystem, especially the spatial light intensity modulation subsystem. sub-system.

In an optional embodiment of the present invention, the laser annealing device further includes a silicon wafer stage 500, the silicon wafer is loaded on the silicon wafer stage 500, and the host machine 00 controls and drives the The silicon wafer is moved horizontally so that the light spot can spread across the surface of the silicon wafer. The silicon wafer stage 500 can also be controlled by the host to drive the silicon wafer to move vertically, so as to meet the depth of focus requirement. Specifically, the wafer loading stage 500 is composed of at least a movable table that can move freely in the horizontal plane, and can carry the silicon wafer, make the silicon wafer move relative to the light spot, and realize annealing of the entire silicon wafer throughout the entire silicon wafer. At the same time, it should also satisfy the need to keep the silicon wafer within the focal depth of the optical subsystem.

In an optional embodiment of the present invention, the annealing device can also move the light spot relative to the silicon wafer by means of vibrating mirrors, etc., so as to spread over the entire silicon wafer, so as to realize the annealing of a single silicon wafer. Specifically, for example, the laser annealing device further includes a vibrating mirror scanning subsystem, which controls the movement of the light spot relative to the silicon wafer, so that the light spot can cover the surface of the silicon wafer.

For the above optional embodiment, the host computer includes a laser light source control subsystem for controlling the laser light source subsystem, an optical control subsystem for controlling the optical subsystem, and a spatial optical control subsystem for controlling the spatial light intensity modulation subsystem. Emphasis on modulation and control subsystems.

It should also be pointed out that as a kind of equipment, it should also have other common subsystems that equipment should have, such as environmental control subsystem, frame subsystem, silicon chip transmission subsystem, etc., and the corresponding control subsystem, in No longer describe them one by one here.

The present invention also provides a laser annealing method, comprising the following steps:

Step 1, annealing the silicon wafer with the surface pattern with the annealing wavelength to be used and the incident angle of the laser incident on the surface of the silicon wafer, and measuring the reflectivity of the silicon wafer surface;

Step 2, making a spatial light intensity modulator, so that the light intensity distribution of the spot where the laser modulated by the spatial light modulator is incident on the surface of the silicon wafer corresponds to the reflectivity of the surface of the silicon wafer, so that the The energy absorbed at each light spot position on the surface of the silicon wafer is consistent;

Step 3, uploading a silicon wafer with the same surface pattern to the workpiece table;

Step 4, controlling the movement of the workpiece table, so that the light spot after passing through the spatial light intensity modulator spreads over the entire surface of the silicon wafer, and completes the annealing of the silicon wafer;

Step 5. Step 3 is repeated until the annealing of all silicon wafers with the same surface pattern is completed.

In an optional embodiment of the present invention, the light transmittance T _θ,λ (x,y) of the laser emitted by the spatial light intensity modulator and the reflectivity R _θ,λ (x,y) of the silicon wafer surface y) and satisfy the following relationship:

Wherein, the light transmittance T _θ,λ (x,y) of the laser refers to the ratio of the laser emitted from the spatial light intensity modulator to the laser incident to the spatial light intensity modulator, and λ is the ratio of the incident light wavelength, θ is the incident angle of the incident light, and (x, y) represent the position coordinates at the surface of the silicon wafer.

In an optional embodiment of the present invention, both the spatial light intensity modulator and the silicon wafer are discretized into several spatial grid points during annealing, and the reflectance corresponding to adjacent spatial grid points on the spatial light intensity modulator The maximum distance max(△x,△y) allowed for value selection needs to satisfy:

Wherein, the Δx is the distance between the adjacent spatial grid points on the silicon wafer along the X direction, the Δy is the distance between the adjacent spatial grid points on the silicon wafer along the Y direction, and the is the characteristic thermal diffusion length, satisfying D is the thermal diffusivity, and τ is the exposure time experienced by a point on the surface of the silicon wafer.

In an optional embodiment of the present invention, the step 4 further includes controlling the spatial light modulator to move synchronously with the workpiece table so that the light spot after passing through the spatial light modulator covers the entire surface of the silicon wafer.

In summary, the present invention proposes a laser annealing device and a laser annealing method, the main content of which is based on the reflectivity distribution of the target silicon wafer to be annealed, using the corresponding spatial light intensity modulation subsystem to make the silicon wafer to be annealed The energy absorbed throughout the sheet is uniform, thereby eliminating the pattern effect and ensuring the consistency of device performance.

Claims (16)

1. a kind of laser anneal device, it is characterised in that: including host, laser light source subsystem, optical subsystem, spatial light intensity Modulation subsystem and temperature monitoring subsystem, in which:

The laser light source subsystem, is controlled by the host, generates and exports laser；

The temperature monitoring subsystem, the temperature at laser irradiating position described in monitoring wafer surface, and feed back to the host；

The optical subsystem is controlled by the host, carries out shaping and biography to the laser of laser light source subsystem output It is defeated, obtain the hot spot of optical power detection；

The spatial light intensity modulation subsystem is modulated by the laser that host control is emitted the optical subsystem, Keep the light distribution for being incident to the hot spot at the silicon chip surface corresponding with the reflectivity of the silicon chip surface, so that institute State that absorbed energy at each facula position of silicon chip surface is consistent, and the energy can be determined according to the temperature monitored；

Laser light source subsystem, optical subsystem and sky described in feedback control of the host according to the temperature monitoring subsystem Between intensity modulation subsystem.

2. laser anneal device as described in claim 1, it is characterised in that: the laser light source subsystem include one or Multiple lasers, each laser is by the host independent control.

3. laser anneal device as described in claim 1, it is characterised in that: the optical subsystem includes:

Laser spot detection mechanism carries out the measurement of energy and corresponding facula position to the laser of laser light source subsystem output And feed back to host；

Energy attenuation mechanism is controlled by the host, according to the measurement result of the laser spot detection mechanism, to the laser light source The energy of the laser of subsystem output is controlled；

Beam-expanding collimation mechanism is controlled by the host, carries out light spot shape to the laser after the energy attenuation mechanism controls Control；

And even ray machine structure, the laser facula after being controlled by host control shape carries out shaping, and then obtains uniformly Hot spot.

4. laser anneal device as described in claim 1, it is characterised in that: the spatial light intensity modulation subsystem includes space Light intensity modulator and the modulator loading stage for loading the spatial light intensity modulator, in which:

The spatial light intensity modulator, is controlled by the host, and the uniform hot spot being emitted after the optical subsystem is saturating Penetrate or reflex to the silicon chip surface.

5. laser anneal device as claimed in claim 4, which is characterized in that is be emitted after the spatial light intensity modulator swashs The light transmittance T of light_θ,λThe reflectivity R of (x, y) and the silicon chip surface_θ,λ(x, y) is adapted, and meets following relationship:

Wherein, the light transmittance T of the laser_θ,λ(x, y) refers to the laser being emitted from the spatial light intensity modulator and is incident to described The ratio between the laser of spatial light intensity modulator, λ are the wavelength of incident light, and θ is the incidence angle of incident light, and (x, y) indicates the silicon wafer Position coordinates at surface.

6. laser anneal device as described in claim 4 or 5, which is characterized in that when annealing the spatial light intensity modulator and The silicon wafer by it is discrete be several space lattices, reflectivity corresponding to adjacent space lattice point on the spatial light intensity modulator Carrying out the permitted maximum distance max of value (△ x, △ y) needs to meet:

Max (△ x, △ y)≤(0.1~1) * l；

Wherein, the △ x be the silicon wafer on adjacent space lattice point along X to distance, the △ y be the silicon wafer on adjacent vacant Between lattice point along the distance of Y-direction, the l is characterized thermal diffusion length, meetsD is thermal diffusivity, and τ is the silicon wafer Some time for exposure experienced at surface.

7. laser anneal device as described in claim 1, it is characterised in that: the host includes controlling the laser light source point Laser light source control subsystem, the optics control subsystem of the control optical subsystem and the control spatial light intensity of system The spatial light intensity modulation control subsystem of modulation subsystem.

8. laser anneal device as described in claim 1, it is characterised in that: further include silicon-chip loading platform, the silicon slice loading The silicon wafer is driven to be horizontally moved in the silicon-chip loading platform, and by host control, so that hot spot can be all over And the silicon chip surface.

9. laser anneal device as claimed in claim 8, it is characterised in that: the silicon-chip loading platform passes through the control of silicon-chip loading platform Subsystem processed is controlled by the host.

10. laser anneal device as claimed in claim 8, it is characterised in that: the silicon-chip loading platform can also be by the master It is vertically movable that machine control drives the silicon wafer to carry out, to meet depth of focus demand.

11. laser anneal device as claimed in claim 4, it is characterised in that: the spatial light intensity modulation subsystem further includes Spatial light intensity modulates imaging unit, zooms in or out to the hot spot after the spatial light intensity modulators modulate.

12. laser anneal device as described in claim 1, which is characterized in that further include vibration mirror scanning subsystem, described in control The relatively described silicon wafer movement of hot spot, enables the hot spot throughout the silicon chip surface.

13. a kind of laser anneal method, which comprises the following steps:

Step 1, with proposed adoption annealing wavelength and laser light incident to silicon chip surface incidence angle, to the silicon wafer with picture on surface It anneals, measures the reflectivity of the silicon chip surface；

Step 2, production spatial light intensity modulator, make by the modulated laser light incident of the spatial light modulator to the silicon wafer The light distribution of hot spot at surface is corresponding with the reflectivity of the silicon chip surface, so that each facula position of the silicon chip surface It is consistent to locate absorbed energy；

One silicon wafer with similar face pattern is uploaded to work stage by step 3；

Step 4, the control work stage movement, make the hot spot after the spatial light intensity modulator throughout entire silicon wafer table The annealing of the silicon wafer is completed in face；

Step 5 repeats step 3, until completing the annealing of all silicon wafers with similar face pattern.

14. laser anneal method as claimed in claim 13, it is characterised in that: be emitted after the spatial light intensity modulator The light transmittance T of laser_θ,λThe reflectivity R of (x, y) and the silicon chip surface_θ,λ(x, y) is adapted, and meets following relationship:

Wherein, the light transmittance T of the laser_θ,λ(x, y) refers to the laser being emitted from the spatial light intensity modulator and is incident to described The ratio between the laser of spatial light intensity modulator, λ are the wavelength of incident light, and θ is the incidence angle of incident light, and (x, y) indicates the silicon wafer Position coordinates at surface.

15. laser anneal method according to claim 13 or 14, which is characterized in that spatial light intensity modulator when annealing With the silicon wafer by it is discrete be several space lattices, reflection corresponding to adjacent space lattice point on the spatial light intensity modulator Rate, which carries out the permitted maximum distance max of value (△ x, △ y), to be needed to meet:

Max (△ x, △ y)≤(0.1~1) * l；

Wherein, the △ x be the silicon wafer on adjacent space lattice point along X to distance, the △ y be the silicon wafer on adjacent vacant Between lattice point along the distance of Y-direction, the l is characterized thermal diffusion length, meetsD is thermal diffusivity, and τ is the silicon wafer Some time for exposure experienced at surface.

16. laser anneal method as claimed in claim 13, which is characterized in that the step 4 further includes controlling the space Optical modulator is moved synchronously with the work stage, makes the hot spot after the spatial light modulator throughout entire silicon chip surface.