Photoresist inspection apparatus, photoresist inspection method using the same, and electron beam exposure apparatus
According to example embodiments, there is provided a photoresist inspection method. The photoresist inspection method includes: providing a photoresist on a substrate; irradiating the photoresist with an electron beam and an excitation beam; detecting fluorescent light generated by the photoresist in response to the excitation beam; and evaluating the photoresist based on the fluorescent light.
1. A photoresist inspection method comprising:
providing a photoresist on a substrate;
irradiating the photoresist comprising a plurality of fluorophores with an electron beam and an excitation beam;
detecting a fluorescent light generated by the photoresist in response to the excitation beam; and
evaluating the photoresist based on the fluorescent light, wherein the evaluating of the photoresist comprises generating a histogram of magnitudes of distance movement of the fluorophores based on a vector map indicating movements of the plurality of fluorophores in the photoresist due to exposure of the electron beam.
2. The photoresist inspection method of claim 1 , wherein the evaluating of the photoresist comprises quantitatively evaluating characteristics of the photoresist.
3. The photoresist inspection method of claim 1 , wherein the photoresist is irradiated by the excitation beam before the photoresist is irradiated by the electron beam and after the photoresist irradiated by the electron beam.
4. The photoresist inspection method of claim 1 , wherein the providing of the photoresist on the substrate comprises:
providing the plurality of fluorophores to a photoresist material so that the plurality of fluorophores are uniformly and homogeneously dispersed in the photoresist material; and
applying the photoresist material, in which the plurality of fluorophores are uniformly and homogeneously dispersed, on the substrate so that the photoresist is on the substrate.
5. The photoresist inspection method of claim 4 , wherein the plurality of fluorophores are physically mixed with the photoresist or chemically combined with the photoresist.
6. The photoresist inspection method of claim 4 , wherein detecting the fluorescent light generated by the photoresist in response to the excitation beam comprises generating an electrical signal corresponding to an image of the photoresist comprising locations the plurality of fluorophores based on the fluorescent light.
7. The photoresist inspection method of claim 6 , wherein the evaluating the photoresist based on the fluorescent light comprises evaluating the photoresist based on the electrical signal generated by a detector.
8. The photoresist inspection method of claim 4 , wherein the electron beam is generated by an electron beam optical system, the excitation light is generated by an excitation light source, and fluorescent light is detected by a detector, and wherein the excitation light source and the detector comprise an oblique optical system and the electron beam optical system comprises a vertical optical system.
9. The photoresist inspection method of claim 1 , wherein the plurality of fluorophores are configured to generate the fluorescent light in response to the excitation beam.
10. The photoresist inspection method of claim 9 , wherein detecting the fluorescent light comprises detecting fluorescent light generated by the plurality of fluorophores of the photoresist repeatedly at time intervals while simultaneously irradiating the photoresist with the excitation beam, the excitation beam comprising an electron beam, and wherein the evaluating of the photoresist comprises generating a plurality of images of the photoresist comprising locations of the plurality of fluorophores generated based on the fluorescent light detected at the time intervals.
11. The photoresist inspection method of claim 9 , wherein the evaluating of the photoresist is further performed based on a standard deviation of density changes of the plurality of fluorophores in the photoresist before and after exposure of the electron beam.
12. The photoresist inspection method of claim 9 , wherein the evaluating of the photoresist further comprises calculating a vertical level change of the photoresist due to the electron beam based on a standard deviation of density changes of the plurality of fluorophores in the photoresist before and after exposure of the electron beam.
13. The photoresist inspection method of claim 1 , wherein the electron beam is generated by an electron beam optical system, the method further comprising monitoring contamination of an electron beam optical system based on the fluorescent light.