JPH05283356A - Laser irradiation device - Google Patents

Abstract

PURPOSE:To provide a laser irradiation device having good accuracy of irradiation position control which can carry out a treatment rapidly with high producibility without a waste of time for moving and stopping an irradiation object. CONSTITUTION:Laser irradiation is performed for a part of an irradiation object 1 such as a semiconductor wafer. An operation for performing laser irradiation for other part of the irradiation object 1 is performed continuously at least a plurality of times for the irradiation object 1. The irradiation object 1 is moved relatively to a laser irradiation part continually and laser pulse is emitted when laser irradiation positions 1a 1 to 1e of the irradiation object 1 correspond to the laser irradiation part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser irradiation device. INDUSTRIAL APPLICABILITY The present invention can be used, for example, in the case of performing laser annealing by laser irradiation in manufacturing a semiconductor device.

[0002]

2. Description of the Related Art A conventional laser irradiation apparatus, for example, a laser annealing apparatus used for laser heating a semiconductor wafer in manufacturing a semiconductor device, does not normally irradiate the entire surface of the object to be irradiated, but one element. Irradiation is performed (one chip) at a time, or a plurality of elements are irradiated as a block and this is repeated, and the entire surface is irradiated.

As described above, in an excimer laser annealing apparatus in which one or a plurality of semiconductor device regions are collectively irradiated, but the entire wafer is not collectively irradiated, conventionally, when irradiation of one irradiation region is completed. , Stop the laser light, move the optical system to the stationary sample, irradiate the next laser light at the place corresponding to the next irradiation area of the wafer to be irradiated, repeat this, and repeat the wafer. The entire surface is annealed (note that, as a known technique of a beam annealing apparatus, Japanese Patent Laid-Open No. 1-276622,
There is one described in No. 1-276623).

FIG. 4 shows a schematic view of such a conventional device. In FIG. 4, 1 is a semiconductor wafer that is an irradiation target placed on the sample table 30, 24 is an excimer laser light source that is an annealing light source, and 25 is a sample chamber. 27 'is a filter, 27 is a mirror, 28' is a beam uniform shaping device,
An optical system is constituted by these, and the beam uniform shaping device 28 'is additionally provided with an XY stage for driving this optical system so as to move the optical system. However, with this method, the accuracy of the irradiation position control deteriorates.

In order to improve the above-mentioned points, the sample stage may be moved according to the example of the stepper (projection exposure apparatus). However, as its name implies, the stepper adopts a step-and-repeat method, and this method moves the sample stage and performs light irradiation when the sample stage is stationary.

However, this method is disadvantageous in improving productivity because the acceleration / deceleration time for starting and stopping the movement of the sample stage and the time until settling are wasted.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, has a good accuracy of irradiation position control, and promptly without wasting time for moving and stopping the irradiated body. An object of the present invention is to provide a laser irradiation device capable of performing processing with high productivity.

[0008]

According to the invention of claim 1 of the present application, laser irradiation is performed on a part of an irradiation target, and then laser irradiation is continuously applied on another part of the irradiation target. In the laser irradiation device that performs laser irradiation at least a plurality of times on the irradiation target, the irradiation target is continuously moved relative to the laser irradiation unit, and the laser irradiation position of the irradiation target is laser irradiation. A laser irradiation device configured to emit a laser pulse when it corresponds to a part, and achieves the above object.

According to the invention of claim 2 of the present application, laser irradiation is performed only when the laser irradiation position of the object to be irradiated and the laser irradiation portion correspond to each other in the collective irradiation possible position. The laser irradiating device according to claim 1, which has a constant value, thereby achieving the above object.

According to the invention of claim 3 of the present application, a semiconductor wafer having a plurality of semiconductor device regions is irradiated with a laser, and one semiconductor device region is irradiated in one irradiation, or a plurality of semiconductor device regions are irradiated. The laser irradiation apparatus according to claim 1 or 2, which is configured to irradiate all of the laser beams at one time, thereby achieving the above object.

According to the invention of claim 4 of the present application, the deviation of the irradiation region due to the relative movement of the irradiation object is adjusted by the margin width for separating the semiconductor device provided around the semiconductor device. It is a laser irradiation apparatus of Claim 3, Comprising: By this, the said objective is achieved.

[0012]

According to the invention of the present application, since the irradiation target can be moved, the irradiation position can be controlled accurately.

Further, the movement is performed by connecting, and the irradiation light is emitted in a pulsed manner so that the irradiation is performed at a place corresponding to the irradiation area, so that there is no waste of time for stopping and moving. , Can increase productivity.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. It should be understood that the present invention is not limited to the examples below.

Example 1 In this example, the present invention is applied to a laser annealing apparatus when a semiconductor wafer is irradiated with laser to form a semiconductor device.

In this embodiment, as shown in FIG.
Laser irradiation is performed on a part of the semiconductor device that is the irradiation target 1 (for example, a portion indicated by 1a in the figure), and then laser irradiation is performed on another part of the irradiation target 1 (for example, a portion indicated by 1b in the drawing). The laser irradiation is continuously performed at least a plurality of times on the irradiation target 1, and the semiconductor device which is the irradiation target 1 is continuously moved (in the X direction and in FIGS. 1B and 1C). A movement in the Y direction is shown), and a laser pulse is emitted when the laser irradiation position of the irradiation target 1 corresponds to the laser irradiation portion.

The part to be irradiated at one time (batch irradiation part) is
The semiconductor element may be one chip, or a plurality of chips may be collectively irradiated.

FIG. 3 shows the structure of the laser irradiation apparatus of this embodiment. The host computer 21 sends a start command to the control unit 22, and the control unit 22 controls the sample stage control unit 2
Send sample stand start command to 3. The sample table 29 is
29A for X-axis and 29B for Y-axis are stacked in two stages,
It is driven by each linear motor 30A, 30B. The sample stands 29A and 29B move as shown in FIGS.

FIG. 2 is an enlarged view of the irradiated area shown by reference numeral 11 in FIG. 1 (a). For example, when the laser length measuring device 28 senses that the laser irradiation region 12 has reached the position where the laser irradiation region 12 covers the semiconductor device region 1e, the control unit 22 judges this and sends an irradiation command to the excimer laser 24. The irradiated laser light is introduced into the processing chamber (sample chamber) 25 through the window 26 of the sample chamber via the mirror 27, and is irradiated to the irradiation target 1 (semiconductor wafer) which is a sample. Since the laser irradiation time is several tens of ns, assuming that the moving speed of the sample stage is 1 m / s, only 10 nm moves during this period. Since the semiconductor device separating margin 13, which is a so-called scribe line, is several tens of μm, if this moving amount is absorbed here, the laser beam is not irradiated to the adjacent region (see FIG. 2).

Although a linear motor is used in this embodiment, a rotary motor may be used and a driving force may be transmitted from the outside of the sample chamber to the sample chamber. Other,
The configuration can be changed as appropriate.

According to the present embodiment, the position of the sample stage that continues to move at a constant speed is measured by the laser interferometer even if the sample stage is mechanically moved as fast as possible, and the instantaneous time of, for example, about 40 ns is measured. Since only the excimer laser irradiation is performed, the accuracy of the irradiation position is high, and since the sample stage does not stop midway, the throughput is also higher than that of the step-and-repeat method, which is advantageous.

[0022]

As described above, according to the laser irradiation apparatus of the present invention, the irradiation position is controlled with high accuracy, and the time for moving and stopping the irradiation object is not wasted.
It is possible to quickly perform processing with high productivity.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a laser irradiation device according to a first embodiment.

FIG. 2 is an enlarged view of an irradiation area in the first embodiment.

FIG. 3 is a configuration diagram of a laser irradiation device according to a first embodiment.

FIG. 4 is a configuration diagram of a conventional laser irradiation device.

[Explanation of symbols]

 1 Irradiation object (semiconductor wafer) 1a to 1e Irradiation area (irradiation position) 13 Separation margin (scribe line)

Claims (4)

[Claims] 1. An operation of irradiating a part of an object to be irradiated with laser, and then irradiating another part of the object to be irradiated with laser continuously, so that at least a plurality of times of laser irradiation is applied to the object to be irradiated. In the laser irradiation device to be performed, the irradiation target is continuously moved relative to the laser irradiation part, and laser irradiation is configured to emit a laser pulse when the laser irradiation position of the irradiation target corresponds to the laser irradiation part. apparatus. 2. A structure in which the laser light irradiation energy in the irradiation region is constant by performing laser irradiation only when the laser irradiation position of the irradiation target and the laser irradiation portion correspond to each other in the collective irradiation possible position. Item 2. The laser irradiation device according to item 1. 3. A structure for irradiating a semiconductor wafer having a plurality of semiconductor device regions with a laser and irradiating one semiconductor device region in one irradiation or collectively irradiating a plurality of semiconductor device regions. The laser irradiation device according to 1 or 2. 4. The laser irradiation according to claim 3, wherein the deviation of the irradiation region due to the relative movement of the irradiation object is adjusted by a margin width provided around the semiconductor device for separating the semiconductor device. apparatus.