JP3211357B2 - Laser irradiation equipment - Google Patents

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, when performing laser annealing by irradiating a laser in the manufacture of a semiconductor device.

[0002]

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

As described above, in an excimer laser annealing apparatus which irradiates one or a plurality of semiconductor device regions at once, but does not irradiate the whole wafer at one time, conventionally, when one irradiation region is completely irradiated, The laser beam was stopped, the optical system was moved relative to the stationary sample, and the next laser beam irradiation was performed at the place corresponding to the next irradiation area of the wafer to be irradiated, and this was repeated. The entire surface is annealed (Japanese Patent Application Laid-Open No. 1-276622 discloses a beam annealing apparatus).
No. 1-267623).

FIG. 4 is a schematic diagram of such a conventional apparatus. In FIG. 4, reference numeral 1 denotes a semiconductor wafer, which is an object to be irradiated, mounted on a sample table 30, reference numeral 24 denotes an excimer laser light source as a light source for annealing, and reference numeral 25 denotes a sample chamber. 27 'is a filter, 27 is a mirror, 28' is a beam uniform shaping device,
These components constitute an optical system. The beam uniform shaping device 28 'is provided with an XY stage for driving the optical system so as to move the optical system. However, in this method, the accuracy of irradiation position control deteriorates.

[0005] In order to improve the above point, the sample stage may be moved in accordance with the example of a stepper (projection exposure apparatus). However, as the name implies, the stepper employs a step-and-repeat method, in which the sample stage is moved and light is emitted when the sample stage is stationary.

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

[0007]

An object of the present invention is to solve the above-mentioned problems of the prior art, to provide a high accuracy of irradiation position control, and to quickly and without wasting time for moving and stopping an irradiation object. An object of the present invention is to provide a laser irradiation apparatus which can perform processing with high productivity.

[0008]

According to the first aspect of the present invention, an operation of irradiating a part of an object to be irradiated with a laser and then irradiating another part of the object to be irradiated with the laser is performed continuously. ,
In a laser irradiation apparatus that performs at least a plurality of laser irradiations on an object to be irradiated, the object to be irradiated is continuously moved relative to the laser irradiation part, and the laser irradiation position of the object to be irradiated is moved to the laser irradiation part. and configured to emit laser pulses when corresponding, and a plurality of semiconductor devices territory
Irradiating the semiconductor wafer with the laser
Irradiate one semiconductor device area in one irradiation
Or a configuration for simultaneously irradiating a plurality of semiconductor device regions;
A laser irradiation apparatus, which achieves the above object.

According to the invention of claim 2 of the present application, the laser irradiation is performed only when the laser irradiation position of the object to be irradiated corresponds to the laser irradiation part at the collectively irradiable position, so that the laser light irradiation energy of the irradiation area is improved. 2. The laser irradiation apparatus according to claim 1, wherein the laser irradiation apparatus has a configuration in which a constant is achieved.

The invention according to claim 3 of the present application has a configuration in which a shift of an irradiation area due to a relative movement of an irradiation target is adjusted by a margin width provided around the semiconductor device for separating the semiconductor device. The laser irradiation apparatus according to claim 1, wherein the above object is achieved.

[0011] The invention of the present application has the above configuration,
It achieves the purpose.

[0012]

According to the invention of the present application, the irradiation object can be moved so that the irradiation position can be controlled with high accuracy.

Further, movement done by continuing, so as to pulsed to emit light towards the illumination light, so to perform the irradiation at corresponding to the irradiation area, out waste of time associated with stopping and moving And productivity can be improved.

[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 by the following examples.

Embodiment 1 In this embodiment, the present invention is applied to a laser annealing apparatus for forming a semiconductor device by irradiating a semiconductor wafer with a laser.

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 part indicated by 1a in FIG. 1), and then laser irradiation is performed on another part of the irradiation target 1 (for example, a part indicated by 1b in FIG. 1). The laser irradiation is performed on the object 1 at least a plurality of times continuously, and the semiconductor device as the object 1 is continuously moved (FIG. 1B and FIG. 1C). (Shows movement in the Y direction), and emits laser pulses when the laser irradiation position of the irradiation target 1 corresponds to the laser irradiation part.

The part to be irradiated at a time (collectively irradiated part)
One chip of the semiconductor element may be used, or a plurality of chips may be collectively irradiated.

FIG. 3 shows the configuration 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 sends the start command to the sample stage control unit 2.
A sample stage start command is sent to 3. The sample stage 29 is
29A for X-axis and 29B for Y-axis are two-tiered,
It is driven by each linear motor 30A, 30B. The sample tables 29A and 29B move as shown in FIGS.

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

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

According to this embodiment, even if the sample stage is mechanically moved as fast as possible, the position of the sample stage that keeps moving at a constant speed is measured by the laser interferometer, and the instantaneous time of about 40 ns, for example, is measured. Since only excimer laser irradiation is used, the accuracy of the irradiation position is high, and the sample stage does not stop halfway, so that the throughput is 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 control accuracy is good, and the time for moving and stopping the irradiation object is not wasted.
It is possible to perform processing quickly and with high productivity.

[Brief description of the drawings]

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

FIG. 2 is an enlarged view of a region to be irradiated according to the first embodiment.

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

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Irradiated object (semiconductor wafer) 1a-1e Irradiated area (irradiated position) 13 Separation margin (scribe line)

Claims (3)

(57) [Claims] 1. An operation of irradiating a part of an object to be irradiated with a laser and then irradiating another part of the object to be irradiated with laser at least a plurality of times to the object to be irradiated. In the laser irradiation apparatus to be performed, the object to be irradiated is continuously moved relative to the laser irradiation part, and a laser pulse is emitted when the laser irradiation position of the object corresponds to the laser irradiation part, and A semiconductor wafer having a plurality of semiconductor device regions
Laser irradiation and one half irradiation
Irradiate a semiconductor device area or
A laser irradiation device configured to collectively irradiate the area . 2. A structure in which laser irradiation is performed only when the laser irradiation position of the object to be irradiated corresponds to the laser irradiation part at the collectively irradiable position, so that the irradiation energy of the laser light in the irradiation region becomes constant. Item 2. The laser irradiation device according to Item 1. The 3. A displacement of the irradiated region accompanying the relative movement of the object to be irradiated, provided around the semiconductor device, according to claim 1 or has a structure to adjust the margin width for said semiconductor device disconnected
Other laser irradiation apparatus according to 2.