Phase-shift mask

About: Phase-shift mask is a research topic. Over the lifetime, 2088 publications have been published within this topic receiving 18058 citations.

Phase shift mask and phase shift mask blank

Abstract: A half tone type phase shift mask as well as a phase shift mask blank for the mask is formed with a thin film light translucent portion made of essentially, nitrogen, metal, and silicon. The containing rate of each element and ratio in the thin film is specified in a certain range to improve film characteristics, such as acid resistance, photo resistance, conductivity, refractive index rate (film thickness), light transmission rate, etching selectivity, etc. of the light translucent portion. The phase shift mask satisfies optical characteristics (i.e., light transmitting rate and phase shift amount) with high precision, as well as reduces defects in the thin film.

Simple repair method for phase shifting masks

Abstract: A method and apparatus for correcting defects in a phase shift mask to be used in photolithography. More specifically, the method of the invention includes creating a second repair mask which contains phase shifters. Regions surrounding the defects on the first mask are made opaque. The design circuitry located in these defective regions is copied onto the second mask. During a second exposure the design circuitry is placed onto the semiconductor wafer. Therefore, this method and apparatus provides an inexpensive solution to a difficult problem.

Phase-shifting mask topography effects on lithographic image quality

Abstract: The impact of phase-shifting mask topography on wafer exposure was studied via simulations and experimentation using phase-shifting masks fabricated by etching the quartz to define the shifted areas. The influence of the refractive index of the chromium layer and of the profile of the chromium patterns was shown to be minimal. On the other hand, the quartz profiles have a large impact on the wafer results. For vertical quartz profiles, the intensity of the light going through the etched portion of the mask is lower than that going through the unetched portion of the mask and varies with feature size. This problem can be addressed either by optimizing the quartz profiles or by biasing the size of the features depending on the type of pattern. >

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 >

Phase-shift mask pattern accuracy requirements and inspection technology

Abstract: Computer simulations and i-line phase shift lithography experiments with programmed 5X phase shift reticle defects were used to investigate the effect of opaque and phase-shift layer defects on sub-half-micron lines. Both the simulations and the experiments show that defects in the phase shift layer print larger than corresponding opaque defects, with 0.3-0.4 micrometers defects affecting sub-half-micron critical dimensions by more than the allowable 10%. Inspection of programmed phase shift defects with a prototype mask inspection system confirmed that the system finds the 0.3-0.4 micrometers phase shift defects critical to sub-half-micron lithography.