This paper describes a noncontact capacitive-sensor metrology sensor developed to measure minimum feature sizes, also called critical dimensions, patterned on photomasks that are used in semiconductor device manufacture. Additionally, this paper describes the test structures printed on photomasks that facilitate linewidth metrology with the new sensor. The metrology sensor is fabricated using a low temperature co-fired ceramic technology and its principle is based on noncontact microcapacitance measurements of features on chrome-on-glass reticles.Index Terms-Critical dimensions (CDs), linewidth, low temperature co-fired ceramic technology (LTCC), noncontact capacitive sensor, photomask metrology.
ABSTRACT-Several concepts (and assumptions) from the literature for porous metals and ceramics have been synthesized into a consistent model that predicts an admissibility Iirnit on a material's porous yield surface. To ensure positive plastic work, the rate at which a yield surface can collapse as pores grow in tension must be constrained.
INTRODUCTION:Brannon [1999] has developed a porosity model that includes features needed to model a 10% porous phase transforming ferroelectric ceramic of interest to us. Fig. 1 shows a good prediction of shock compression data of Furnish et al. [2000].
This paper describes a novel non-contact capacitive-sensor metrology tool developed for chrome photomasks. This work further describes suitable types of test structures printed on photomasks appropriate for linewidth metrology. The Critical Dimension (CD) metrology sensor is developed using a Low Temperature Co-Fired Ceramic (LTCC) technology to reduce the effects of parasitic capacitances. The sensor is based on non-contact micro-capacitance measurements of features on chrome-on-glass reticles. The CD-extraction algorithms based on the capacitance measurements are formulated from extensive evaluation with a Maxwell1 simulator. The purpose of the non-contact micro-capacitive sensor is to measure chrome-feature linewidths in the range of 0.4 tm -0.5 jtm. These dimensions correspond to a O.18-jtm process on a 4X mask.
This paper describes limitations of conventional methods of extracting sheet resistance from four-terminal sheet resistors incorporated into electrical linewidth test structures that are patterned in (110) monocrystalline silicon-on-insulator (SOI) films. Nonplanar sections of these structures render the extraction of sheet resistance by conventional techniques subject to systematic errors. The errors are addressed here by algorithms incorporating the results of finite-element currentflow analysis. The intended end application is to facilitate the use of the uniquely high repeatability and low cost of electrical critical dimension (CD) metrology as a secondary reference in a traceability path for CD-reference artifacts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.