Photomask and Exposure Method

Abstract

The purpose of this invention is to suppress dimensional conversion differences generated during exposure. An embodiment of the photomask includes a splicing region having a first end at one end and a second end at a predetermined distance inward from the first end, and comprises: a substrate; a reflective layer disposed on a first surface of the substrate to reflect light; and a light-shielding pattern disposed on a second surface of the reflective layer opposite to the substrate, comprising a light-absorbing layer for absorbing light; and configured such that, in the splicing region, the light reflection intensity is lower on the first end side than on the second end side.

Claims

1. A photomask including a splicing region; the splicing region having: a first end located at a position corresponding to one end of the photomask; and a second end located at a position extending inward from the first end of the photomask at a predetermined distance; and the photomask comprising: a substrate; a reflective layer disposed on a first surface of the substrate for reflecting light; and a light-shielding pattern disposed on a second surface of the reflective layer opposite to the substrate, including a light-absorbing layer for absorbing the light; and the photomask being configured such that, in the splicing region, the intensity of light reflection is lower at the first end than at the second end.

2. The photomask of claim 1, wherein the light-shielding pattern comprises: a first light-shielding pattern disposed on the second surface of the reflective layer including the splicing area; and a second light-shielding pattern disposed on the splicing area of ​​the second surface of the reflective layer; and the coverage of the second light-shielding pattern is greater at the first end side of the splicing area than at the second end side.

3. The photomask as claimed in claim 2, wherein the coverage of the second light-shielding pattern increases in stages from the second end of the splicing area toward the first end.

4. The photomask of claim 2, wherein the first light-shielding pattern is disposed in the region between the aforementioned one end and the other end opposite to the aforementioned one end.

5. The photomask of claim 1, wherein the light-shielding pattern comprises: a first light-shielding pattern disposed on the second surface of the reflective layer including the splicing area; and a second light-shielding pattern disposed on the splicing area of ​​the second surface of the reflective layer; and in the second light-shielding pattern, the light-absorbing layer is thicker at the first end side of the splicing area than at the second end side.

6. The photomask of claim 1, wherein the reflective layer is thinner at the first end side of the splicing area than at the second end side.

7. A photomask comprising: a substrate; a reflective layer disposed on a first surface of the substrate for reflecting light; a light-shielding pattern disposed on a second surface of the reflective layer opposite to the substrate, including a light-absorbing layer for absorbing the light; and a protective film disposed at a predetermined distance from the light-shielding pattern and facing the first surface; wherein the protective film includes a region having a first end at a position corresponding to one end of the substrate, and a second end at a position corresponding to a position extending inward from the first end of the substrate at a predetermined distance; and wherein the protective film has a first layer that thickens from the second end toward the first end.

8. The photomask as claimed in claim 7, wherein the first layer is a protective layer that protects the light-shielding pattern.

9. The photomask of claim 7, wherein the protective film further comprises: a second layer covering the third surface of the first layer opposite to the light-shielding pattern; and the first layer being an oxidation-inhibiting layer that inhibits oxidation of the second layer; and the second layer being a protective layer that protects the light-shielding pattern.

10. An exposure method comprising: using a first photomask to expose a first region extending from one end of an irradiation area disposed on a wafer to a position extending a first distance inward into the irradiation area; and using a second photomask to expose a second region extending from the other end of the irradiation area to a position extending a second distance inward into the irradiation area and reaching a position within the first region, thereby doubling the exposure of a third region located at the center of the irradiation area and exposing the entire irradiation area; wherein the first and second photomasks comprise: a splicing region corresponding to the third region, having a first end at a position corresponding to one end of each of the first and second photomasks, and having a second end at a position extending a predetermined distance inward from the first and second end of each of the first and second photomasks; and wherein the first and second photomasks comprise: a substrate; A reflective layer disposed on a first surface of the substrate to reflect light; and a light-shielding pattern disposed on a second surface of the reflective layer opposite to the substrate, comprising a light-absorbing layer that absorbs the light; and the first and second photomasks are configured such that, in the splicing area, the light reflection intensity is lower at the first end side than at the second end side.

11. An exposure method comprising: using a first photomask to expose a first region extending from one end of an irradiation area of ​​a wafer to a position extending a first distance inward into the irradiation area; and using a second photomask to expose a second region extending from the other end of the irradiation area to a position extending a second distance inward into the irradiation area and reaching the first region, thereby doubling the exposure of a third region located at the center of the irradiation area and exposing the entire irradiation area; wherein the first and second photomasks comprise: a substrate; a reflective layer disposed on a first surface of the substrate for reflecting light; a light-shielding pattern disposed on a second surface of the reflective layer opposite to the substrate, comprising a light-absorbing layer for absorbing the light; and a protective film disposed at a predetermined distance from the light-shielding pattern and facing the first surface; wherein the protective film comprises the following region: Corresponding to the third region mentioned above, a first end is provided at a position corresponding to one end of each of the first and second photomasks, and a second end is provided at a position corresponding to a position that extends inward from one end of each of the first and second photomasks by a predetermined distance; and the protective film has: a first layer that thickens from the second end toward the first end.

Images