KR100205518B1 - Exposed light device and exposed light method - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus and an exposure method, and more particularly, to an exposure apparatus for exposing a photoresist layer coated on a transparent glass substrate to light, a light source for generating light having a concentrated property and directionality, An optical system for irradiating a lower portion of the substrate with a back surface light so as to expose the upper surface of the photoresist film; an optical sensor for sensing light transmitted through the lower portion of the substrate after exposing the photoresist film; The amount of light detected by the photosensor after the shutter is turned on is accumulated when a light amount required for exposure of the photosensitive film applied on the substrate is set, A light amount integrator for comparing the set light amount with the accumulated light amount, Quot; off " the shutter of the " on " state. Therefore, by sensing and integrating the light transmitted through the substrate, the amount of light irradiated on the photosensitive film can be made constant.

Description

Exposure Apparatus and Exposure Method

FIG. 1 is a schematic view of an exposure apparatus according to the prior art; FIG.

FIG. 2 is a flow chart showing an exposure method using the exposure apparatus of FIG. 1;

FIG. 3 is a schematic view of an exposure apparatus according to the present invention. FIG.

4 is a flow chart showing an exposure method using an exposure apparatus of FIG. 3;

DESCRIPTION OF THE REFERENCE NUMERALS

31: Exposure device 33: Light source

35, 39: first and second plane mirrors 37: optical system

41: substrate 43: light sensor

45: light amount integrator 47: shutter adjuster

49; shutter

The present invention relates to an exposure apparatus and an exposure method, and more particularly, to a method of manufacturing a thin film transistor, in which a good photosensitive film pattern is obtained by detecting the amount of light transmitted through a photoresist film upon back exposure, To an exposure apparatus and an exposure method.

In general, a staggered structure in which amorphous silicon is used as a semiconductor layer in a thin film transistor of a liquid crystal display device is distinguished by an inverted staggered type in a lower portion of the source and drain electrodes and a staggered type in the upper portion. The inverse stagger type has a smaller plasma damage to amorphous silicon and a higher electron mobility than a stagger type at the time of film formation.

In the inverse stagger type thin film transistor, an etch stop layer is formed on the gate to prevent the semiconductor layer used as a channel when the source and drain electrodes are formed from being etched. The etch stopping layer is formed by back-side exposure using a gate formed at the bottom as a mask. In order to make the capacitance between the gate electrode and the drain electrode uniform, the overlapping portion must be constant. In this case, since the overlapping portion of the gate electrode and the drain electrode is not constant, the quality of the image is deteriorated when the capacitance is changed, so that the exposure amount of the photoresist layer must be adjusted to be constant at the time of backside exposure.

1 is a schematic view of an exposure apparatus 11 according to the prior art.

An exposure apparatus 11 for irradiating light to a lower portion of a substrate 21 made of transparent glass according to the related art and coated with a photoresist (not shown) on the top thereof exposes the light source 13, the first, And includes a flat mirror 15 (19), an optical system 17, a substrate 21, an optical sensor 23, a time setting timer 25, a shutter controller 27 and a shutter 29.

The light source 13 generates light having a concentrated property and directionality.

The first plane mirror 15 changes direction so that light generated in the light source 13 is incident on the optical system 17.

The optical system 17 includes a condenser lens for preventing loss of incident light and a fly's eye lens for evenly dispersing the light to improve the uniformity of light intensity.

The second plane mirror 19 changes the direction so that the light having passed through the optical system 17 is incident on the substrate 21.

The light sensor 23 measures the illuminance per unit area of the light incident on the substrate 21 and detects the light amount.

The shutter 29 is turned 'on' or 'off' to block light from being irradiated or irradiated to the substrate 21.

The time setting timer 25 sets a predetermined exposure time in accordance with the illuminance detected by the photosensor 23 when the necessary exposure amount of the substrate 21 is set.

The shutter adjuster 27 controls the shutter 29 to be turned 'on' or 'off' by the time setting timer 25.

FIG. 2 is a flow chart showing an exposure method using the exposure apparatus 11 of FIG. An exposure method using the exposure apparatus 11 shown in FIG. 1 will be described with reference to FIG.

The exposure amount A1 necessary for forming a pattern on the substrate 21 by exposing the photosensitive film by back exposure is set. This exposure amount is obtained by an experiment. The luminous intensity I1 of the light generated in the light source 13 and reaching the substrate 21 through the first plane mirror 15, the optical system 17 and the second plane mirror 19 is detected by the optical sensor 23) (S11).

The exposure amount B necessary for exposing the photosensitive film on the substrate 21 is calculated as the illuminance sensed by the photosensor 23 and the time at which the shutter 29 is turned on in the time setting timer 25 A / B) (S12).

The time T1 at which the set shutter 29 is to be turned on is transmitted to the shutter controller 27 which turns the shutter 29 on to cause the substrate 21 to emit the necessary exposure dose A (S13).

Then, the shutter controller 27 causes the shutter 29 to be turned on for a time t1 to be continuously measured so that light is irradiated to the substrate 21, and the 'on' time t1 of the shutter (T1), the shutter 29 is turned on (S14).

At this time, if the 'on' time t1 of the shutter 29 is equal to the set time T1, the shutter 29 is turned off (S15).

As described above, in the conventional exposure apparatus and the exposure method using the same, in order to form a photoresist pattern by back exposure, it is necessary to set the necessary exposure amount, to detect the illuminance of the light before reaching the substrate, The amount of exposure required for exposure is calculated as the illuminance sensed by the optical sensor, and the time at which the shutter is turned on to the time setting timer is set. Then, the set time is transmitted to the shutter controller, and the shutter is turned on during this time to irradiate the substrate with light.

The conventional light modulation apparatus and the exposure method using the light modulation apparatus described above expose the laminated substrate of the light-absorbing material including the material layer of amorphous silicon to the back surface to change the amount of light absorbed depending on the thickness of the laminated material layers It is difficult to precisely control the amount of exposure reaching the photosensitive film.

Accordingly, it is an object of the present invention to provide an exposure apparatus capable of sensing a light transmitted through a substrate during a back-side exposure and irradiating a photosensitive film with a predetermined exposure dose.

It is another object of the present invention to provide an exposure method capable of precisely controlling an amount of exposure reaching a photoresist film regardless of the thickness of material layers made of a material capable of absorbing light including a material layer of amorphous silicon deposited on a substrate during back exposure have.

According to an aspect of the present invention, there is provided an exposure apparatus for exposing a photoresist layer on a substrate, the apparatus comprising: a light source for generating light having a collection property and directionality; a light source for preventing and dispersing light generated from the light source; An optical system for irradiating a lower portion of the substrate with light to improve the uniformity of light emitted from the lower portion of the substrate and exposing the upper portion of the photoresist film to a back exposure; The amount of light required for exposure of the photoresist film coated on the substrate is set to a shutter that controls the substrate to be irradiated or blocked, and the amount of light sensed by the photosensor after the shutter is turned on is accumulated, And a light quantity accumulator for comparing the accumulated light quantity with the light quantity accumulated in the light quantity accumulator, And a shutter that controls "off".

According to another aspect of the present invention, there is provided an exposure method for exposing a photoresist layer on a back surface of a substrate according to the present invention includes the steps of: setting a light exposure amount necessary for forming a pattern by back exposure of a photoresist layer formed on a substrate, A step of turning on a light source to turn on the light source to expose the substrate, thereby exposing the substrate to a back light by the light generated from the light source to expose the photoresist film on the substrate, and sensing light transmitted by the light sensor; Integrating the amount of light sensed by the optical sensor and comparing the amount of light sensed by the optical sensor until the light amount is equal to the set light amount; and turning off the shutter when the amount of light integrated in the light amount integrator becomes equal to the set light amount.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings.

3 is a schematic view of an exposure apparatus 31 according to the present invention.

An exposure apparatus 31 for exposing light to a lower portion of a substrate 41 made of transparent glass according to the present invention and coated with a photoresist film (not shown) on the upper surface thereof includes a light source 33, Mirrors 35 and 39, an optical system 37, an optical sensor 43, a light amount accumulator 45, a shutter controller 47, and a shutter 49.

The light source 33 generates light such as ultraviolet rays, infrared rays, or visible rays to have a concentrated property and a directionality.

The first plane mirror 35 is installed at a predetermined angle with the optical path of the light generated by the light source 33 so that the reflected light enters the optical system 37.

The optical system 37 is composed of a condenser lens and a fly-eye lens. The light reflected by the first plane mirror 35 prevents light from being lost due to scattering and spreading, Thereby improving the uniformity of the roughness.

The second plane mirror 39 is installed at a predetermined angle with the optical path of the light passing through the optical system 37 so that the reflected light is incident on the substrate 41.

The photosensor 43 irradiates the substrate 41 from the second plane mirror 39 to expose the photosensitive film, and senses the amount of the transmitted light to detect the degree of exposure of the substrate 41.

The light amount accumulator 45 sets the light amount 12 required for exposure of the photosensitive film applied on the substrate 41. [ Then, after the shutter 49 is turned on by the shutter controller 47, the light amount detected by the optical sensor 43 is accumulated, and the total light amount It and the set light amount 12 Compare until they match.

The shutter controller 47 controls the operation of the shutter 49 to turn on the shutter 49 and drives the light amount integrator 45 to cause the integrated total light amount It to coincide with the set light amount 12 The shutter 49 is turned off.

The shutter 49 is turned 'on' or 'off' by the shutter controller 47 to block the light from being irradiated or irradiated onto the substrate 41.

FIG. 4 is a flowchart showing an exposure method using the exposure apparatus 31 of FIG. An exposure method using the exposure apparatus 31 shown in FIG. 3 will be described with reference to FIG.

The exposure amount 12 necessary for forming a pattern on the back surface of the photosensitive film formed on the substrate 41 is set in the light amount accumulator 45. [ The exposure dose 12 is obtained experimentally by an amount of light enough to sufficiently expose the photosensitive film on the substrate 41 (S21).

When the light source 33 is turned on, the shutter 49 is turned on so that the light generated by the light source 33 passes through the first plane mirror 39, the optical system 37 and the second plane mirror 39 41 are back exposed. At this time, the photosensor 43 exposes the photosensitive film of the substrate 41 and senses the transmitted light (S22).

The light amount integrator 45 integrates the light sensed by the optical sensor 43. The light amount integrator 45 compares the accumulated total light amount It until it is equal to the set light amount 12. If the total light amount It is smaller than the set light amount 12, the shutter 49 is continuously turned on (S23).

When the accumulated light amount It is equal to the set light amount 12, the light amount accumulator 45 transmits to the shutter regulator 47 that the accumulated light amount It and the set light amount 12 are equal . Thus, the shutter adjuster 47 turns off the shutter 49 to prevent light from being further irradiated to the substrate 41 (S24).

As described above, according to the present invention, the amount of exposure required to form a pattern on a photoresist layer formed on a substrate is exposed on a back surface of a photoresist layer formed on a substrate, the backside of the substrate is exposed, the light transmitted through the substrate is detected by an optical sensor, And the shutter is turned on until it is the same as the predetermined exposure amount to expose the substrate.

Accordingly, the present invention has the advantage that the amount of light irradiated on the photosensitive film can be made constant by sensing and integrating the light transmitted through the substrate.

Claims (4)

An exposure apparatus for back exposure of a photoresist film applied on a top of a substrate made of transparent glass, comprising: a light source for generating light having condensing property and directional light; and a light source for preventing and dispersing the light generated from the light source and improving the uniformity An optical system for irradiating a lower portion of the substrate with the upper photoresist film to expose the upper surface of the photoresist film to a back exposure; an optical sensor for sensing light transmitted through the lower portion of the substrate after exposing the photoresist film; The amount of light required for exposure of the photosensitive film applied on the substrate is set and the amount of light sensed by the photosensor after the shutter is turned on is accumulated and the amount of light integrated with the set amount of light And a light amount accumulator for comparing the light amount accumulated in the light amount accumulator with the light amount set in the light amount accumulator, And a shutter controller. The exposure apparatus according to claim 1, further comprising first and second planar mirrors for changing the intensities of light generated from the light source and light that has passed through the optical system. The exposure apparatus according to claim 1, wherein the optical system comprises a condenser lens and a fly-eye lens. An exposure method for exposing a photoresist film coated on a substrate made of transparent glass on a back surface, the method comprising the steps of: setting a light exposure amount necessary for forming a pattern by back exposure of a photoresist film formed on a substrate in a light amount integrator; A step of exposing a photosensitive film on a substrate by light emitted from the light source to the backside of the substrate and sensing the light transmitted by the optical sensor, And comparing the accumulated amount of light with the set amount of light until the amount of light accumulated in the light amount integrator becomes equal to the set light amount.