Showing papers on "Phase-shift mask published in 1990"

Transparent phase shifting mask

Abstract: A transparent phase shifting mask has been demonstrated to improve the resolution of the conventional i-line stepper and to facilitate the fabrication of various deep submicron patterns for VLSI This mask, having a single patterned layer of phase shifter, can be easily fabricated, and it is easy to inspect and repair compared to the conventional phase shifting mask with double patterned layers for the Cr layer and the phase shifter layer The transparent phase shifting mask is promising for fabricating sub-half-micron patterns for 64 M DRAMs >

Mask and projection exposure device and pattern forming method

Abstract: PURPOSE: To obtain sufficient resolution and the depth of a focus in the case of a solid element pattern by using a phase shift mask and a multiple image- forming exposure method, and forming plural images of mask patterns at different positions in the optical axis direction. CONSTITUTION: The phase shift masks are used and the multiple image-forming exposure method is operated especially, under highly coherent illumination, and the distance between the same phase patterns opposite to each other across a light-shielding part is set to a prescribed distance or more in accordance with a space coherency and whether the multiple image-forming exposure method is applied or not. The illumination light to be used has high coherency in the repeated directions of the repeated patterns and comparatively low coherency in the directions perpendicular to the above directions. The form of an effective light source in the face of a secondary light source of a reduction projection exposure device is set to a small one in the repeated directions of the repeated patterns and to a large one in the direction perpendicular to the above directions, thus permitting sufficient resolution and the sufficient depth of the focus to be obtained. COPYRIGHT: (C)1992,JPO&Japio

Production of phase shift mask

Abstract: PURPOSE:To unnecessitate a mask for forming a shifter and to enhance the yield of phase shift masks by forming a photosensitive resin film on the surface of a light shielding pattern on a transparent substrate, uniformly exposing the resin film through the substrate and forming a shifter of the resin film. CONSTITUTION:A light shielding pattern 12 of Cr, etc., is formed on a glass substrate 11 and the entire surface of the substrate 11 on the pattern 12 side is uniformly coated with a positive type resist 13 in a desired thickness. The resist 13 is prebaked, uniformly exposed with g- or i-beams through the substrate 11 and developed. The developed resist is uniformly exposed and post-baked to produce a phase shift mask having a shifter 13 on the pattern 12. When a negative type resist is used in phase of the positive type resist 13, a mask having a shifter 23 can be produced in the same way.

Production of photomask having phase shift layer

Abstract: PURPOSE:To obviate the generation of defects by inserting a stage for removing the outer peripheral parts of a transparent film used for forming phase shifters by wet etching, etc., after formation of this film during the production process. CONSTITUTION:The stage for removing the outer peripheral parts of the transparent film used for forming the phase shifters is inserted before the stage for forming the phase shifter patterns. The cracks based on the nonuniformity of stresses enter the transparent film of the edge parts of the reticule and dust is generated by contact of the edge parts with a holder, etc., while the reticule undergoes the stage in the process for producing the conventional phase shift reticule, but the generation of the dust from the outer peripheral parts of the transparent film is prevented in such a manner, by which the phase shift mask free from defect is formed.

Manufacture of phase shift mask

Abstract: PURPOSE: To form a phase shift mask in an easy process good in controllability by etching back a phase shift material film to form a side wall coat on the side wall of a light-shielding material pattern, and using this side wall coat as a phase shift part. CONSTITUTION: The quartz substrate 1 has a thin etching stopper film 1a on its surface, and on the film 1a the light-shielding material layer 10a made of chromium is formed, then, this layer is patterned, a phase shift material SiO 2 layer 11a is formed on the layer 10a and the pattern, and the side wall coat made of SiO 2 is formed on the side wall of the pattern to form the phase shift part 11. Then, the phase shift material SiO 2 layer 11a is etched on the whole surface so as to remove at least the SiO 2 on the surface but to leave all the side wall coat 11b, and this coat 11b is used as the phase shift part, the light- shielding material pattern 10b is used as the light-shielding part 10 as it is, and the disclosed substrate part between the coat 11b is used as the light transmitting part 12, thus permitting the phase shift mask to be formed in an easy process good in controllability. COPYRIGHT: (C)1992,JPO&Japio