Mask inspection

About: Mask inspection is a research topic. Over the lifetime, 1072 publications have been published within this topic receiving 8696 citations.

Inspection method for charged particle beam mask, inspection apparatus for charged particle beam mask and charged particle beam mask data structure

Abstract: PROBLEM TO BE SOLVED: To inspect masks for transferring patterns by using two or more masks so as to relieve a pseudo defect in a part where no problem is caused from the viewpoint of a device while keeping the inspection accuracy in a pattern region. SOLUTION: A pseudo defect is relieved by dividing a pattern into a stitching part and the other pattern portion on comparing the mask image to mask data and by decreasing the defect detection sensitivity in the stitching part than that in the pattern portion. COPYRIGHT: (C)2005,JPO&NCIPI

System for evaluating a design of a mask, exposure system, method for evaluating a design of a mask, method for manufacturing a semiconductor device and mask

Abstract: A system for evaluating a design of a mask includes: an inspection data memory storing initial inspection data of an initial wafer fabricated by an initial mask; a design tool designing a modified mask based on the initial inspection data; a group of manufacturing tools forming an initial mask chip region with the initial mask and a modified mask chip region adjacent to the initial mask region with the modified mask; an inspection tool inspecting faults in the initial and modified mask chip regions; and an evaluation tool evaluating an improvement of the design of the modified mask.

Phase defect detection with spatial heterodyne interferometry

Abstract: Phase shift techniques introduced in photolithography to further improve resolution produce a new set of challenges for inspection. Unlike the high contrast provided by patterned and unpatterned areas on a binary mask, phase errors do not provide significant contrast changes, since the phase change is imparted by a difference in material thickness. Surface topology measurements can be used to identify phase defects, but methods for surface topology inspection are typically slow or can damage the surface to be measured. In this study, Spatial Heterodyne Interferometry (SHI) has been considered as a possible method for high-speed non-contact phase defect detection. SHI is an imaging technique developed at Oak Ridge National Laboratory that acquires both phase and amplitude information from an optical wavefront with a single high-speed image capture. Using a reflective SHI system, testing has been performed with a mask containing programmed phase defects of various sizes and depths. In this paper, we present an overview of the SHI measurement technique, discuss issues such as phase wrapping associated with using SHI for phase defect detection on photolithographic masks, and present phase defect detection results from die-to-die comparisons on a 248 nm alternating aperture phase shift mask with intentional phase defects.

Mask degradation monitoring with aerial mask inspector

Abstract: As design rule continues to shrink, microlithography is becoming more challenging and the photomasks need to comply with high scanner laser energy, low CDU, and ever more aggressive RETs. This give rise to numerous challenges in the semiconductor wafer fabrication plants. Some of these challenges being contamination (mainly haze and particles), mask pattern degradation (MoSi oxidation, chrome migration, etc.) and pellicle degradation. Fabs are constantly working to establish an efficient methodology to manage these challenges mainly using mask inspection, wafer inspection, SEM review and CD SEMs. Aerial technology offers a unique opportunity to address the above mask related challenges using one tool. The Applied Materials Aera3 TM system has the inherent ability to inspect for defects (haze, particles, etc.), and track mask degradation (e.g. CDU). This paper focuses on haze monitoring, which is still a significant challenge in semiconductor manufacturing, and mask degradation effects that are starting to emerge as the next challenge for high volume semiconductor manufacturers. The paper describes Aerial inspector (Aera3) early haze methodology and mask degradation tracking related to high volume manufacturing. These will be demonstrated on memory products. At the end of the paper we take a brief look on subsequent work currently conducted on the more general issue of photo mask degradation monitoring by means of an Aerial inspector.

Mask inspection device, mask inspection method, and method for producing semiconductor device

Abstract: PROBLEM TO BE SOLVED: To provide a mask inspection device that has higher detection sensitivity, even if the wavelength of a light source is identical. SOLUTION: The mask inspection device 100, according to one embodiment of the present invention adapted to inspect a mask 106 by observing a pattern formed on a mask substrate 106a, is constituted of an objective lens 108 for observing an observation region 120 that is a part of a pattern surface 106d, which is disposed on the opposite side to the pattern surface 106d of the mask substrate 106a; and a lighting means for emitting substantially circular polarized light to the observation region 120. COPYRIGHT: (C)2009,JPO&INPIT