JPS6153727A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To feed back a result of monitor to the shutter system and carry out highly acurate water patterning by monitoring change in amount of light of lamp for lighting on the stage. CONSTITUTION:A light amount monitor sensor 10 is provided on the stage 9 where a water 8 of semiconductor device is placed on the stage 9, change in amount of light of lamp 1 for lighting is monitored with the sensor 10 and a result of detection of sensor 10 is input to an integrator 4. A measured value of light monitor 2 of the lamp house system is input to the other input of integrator 4 and the shutter 3 is controlled with an output of integrator 4. Difference in amount of light before and after a reticle 6 is loaded to a device is detected with the sensor 10 and result of detection is fed back to the shutter system through the integrator 4. This feedback control the shutter 4 with adequate exposing time and realizes high precision water patterning.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a semiconductor device, and in particular, in resist patterning by projection transfer (also referred to as a projection aligner), changes in the light amount of an illumination lamp are monitored and a mask is produced. This invention relates to an improvement in a method of transferring a pattern to a wafer.

[Prior art]

FIG. 1 shows a schematic diagram of a reduction projection exposure apparatus that is conventionally used as a projection transfer apparatus when manufacturing semiconductor devices. In FIG. 1, 1 is an illumination lamp, 2 is a light amount monitor sensor for monitoring changes in the light amount of this lamp 1,
3 is a shutter, 4 is an integrator for integrating the output of the sensor 2, 5 is a condenser lens, 6 is a reticle as a transfer mask, 7 is a reduction lens, 8 is a wafer for transfer, and 9ilL1kA determines the image position. This stage 9 is loaded with a wafer 8 and can be moved arbitrarily in the X and Y axes.

An outline of the operation of the reduction projection exposure apparatus configured as described above will be explained. First, light from the illumination lamp 1 is made incident on the light amount monitor sensor 2, and the output of this sensor 2 is integrated in the integrator 4.

This integrator 4 is used to adjust the opening/closing time of the shutter 3 so that the exposure energy (illuminance×exposure time) is always constant with respect to the exposure time inputted in advance from software.

Next, the shutter 3 controlled by the integrator 4 is opened, and the light from the illumination lamp 1 enters the condenser lens 5 and is guided to the reticle 6 as highly uniform light. This reticle 6 was retracted (the original was passed through the reduction lens 7), and the specified reduction ratio was reduced to 16 degrees, and the stage 9
The pattern of the reticle 6 is transferred onto the wafer 8 whose position has been determined.

However, in resist patterning using such a transfer device, conventionally, changes in the light intensity of the illumination system are monitored, so when all the pellicles are attached on the reticle,
The drawback is that it is not possible to correct exposure energy for changes in transmittance due to pellicle deterioration, etc., and patterning cannot be performed with high accuracy.

[The Princess of Invention]

The invention was developed in order to eliminate the drawbacks of the conventional ones as described above, and by installing a sensor for monitoring the amount of light on the stage and integrating the output of the sensor, the pellicle etc. A method for manufacturing semiconductor devices that can consistently irradiate a wafer with a constant exposure energy even when light intensity changes due to deterioration, and pattern well into an ellipse. is intended to provide. Embodiments of the present invention will be described below with reference to the drawings.

[Embodiments of the invention]

FIG. 2 is a schematic diagram of a reduction projection exposure apparatus for explaining an embodiment of the method of the present invention.The difference from FIG. A light amount monitoring sensor 10 gold is provided, and the output of this sensor 10 is input δ to the integrator 4 similar to the conventional one described above.

In addition, in Figure 2, the same or equivalent parts as in Figure 1 are [
River - indicates a sign.

Next, the operation of the above embodiment will be explained. The method of transferring to the sea urchin . A sensor 10 for monitoring the amount of light is mounted on the stage 9 according to the present invention, and the sensor 10 is used to monitor the amount of final light. This prototype monitoring on the stage 9 is performed for each wafer and will be explained below.

First, (1) Before the reticle 6 is installed, the light amount of the illumination lamp is measured using the light amount monitor sensor 10 on the stage 9. The measured value at this time is 8. Then, (2) the measurement value of the light amount monitor sensor 2 of the lamp house system is added to the measurement value of the sensor 10, and the result is calibrated to the integrator 4. Next, (3) attach the lever 6, and immediately after that, the light amount monitor sensor 10 on the stage 9
Measure the light intensity again. The measured value at this time is assumed to be Al. Next, t4+measurement 1st shift A and A by the sensor 10
Read the difference from i and let this difference C be A-Al. Hereinafter, the input to the integrator 4 will take the form t of the following equation. In other words, the input value is Al +c+.

becomes. At this time, the measured value Al of the head of state monitor sensor 10
is a constant value when the wafer 8 is being transferred and is stored in the storage device in the integrator 4.

The above is the principle of reading the input value of the integrator 40.
Explain the measurement method to the arrow.

(1) After the transfer of the wafer 8 is completed, when the stage 9 moves to the loading position, the light amount monitor sensor 10
The measurement value A1 is measured at . At this time, the sensor 10
It is necessary to place the shutter directly below the optical axis when in the loading position, and when it comes to the loading position, it is necessary to open the shutter 3 with the same exposure time as measured in step 31 above.

(if) This operation is performed for each wafer 8 after the transfer is completed. ''/l, the latest measured value A1 determined by the imaginary monitor sensor 10 is replaced with the measured value A1 in the storage device, and is immediately fed back to the opening/closing timing of the shutter 3.

In this way, by monitoring the exposure energy emitted from the illumination lamp 1 on the stage θ and feeding back changes in the amount of light to the shutter system, it becomes possible to provide an appropriate exposure time. Therefore, when a pellicle or the like is mounted on the reticle 6, it is possible to correct the change in AW light energy due to deterioration of the pellicle and perform patterning with good accuracy.

In the above embodiment, measurement is performed for each wafer, but the number of wafers can be specified by the user. Further, the projection transfer device is not limited to the Inako projection method, but can be similarly applied to a one-to-one projection method.

〔Effect of the invention〕

As described above, according to the present invention, even when a pellicle or the like is installed as a reticle, the light intensity is constantly monitored on the stage, so it is possible to respond to changes in light intensity due to deterioration of the pellicle, and to monitor wafer butter with less precision. It has the effect of being able to carry out cleaning.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a projection transfer device for explaining a conventional example;
Figure m2 is a schematic diagram of a projection transfer apparatus used to explain an embodiment of the method of the present invention. 1... Illumination lamp, 2... Light amount monitor sensor 311@φ shutter, 4... e integrator,
5. Condenser lens, 6. Fist/reticle,
7・e・・Reducing lens, 8・・11e wafer, 9@・・Stage, 10=・・Light level monitor sensor.

Claims (1)

[Claims] In resist patterning by projection transfer in which a mask pattern is transferred to a wafer on a stage, a change in the light amount of an illumination lamp is monitored on the stage, and the monitoring result is fed back to a shutter system. Production method.