Dyed positive photoresist employing curcumin for notching control

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Journal of the Electrochemical Society; (United States)

DOI:https://doi.org/10.1149/1.2096604· OSTI ID:5045341

Renschler, C L; Lemen, E K; Rodriquez, J L; Stiefeld, R E ^[1]

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1. Sandia National Labs., Albuquerque, NM (United States)

A variety of dyes have been proposed as absorbers for photoresists. The nonbleachable absorbance incorporated in this way can result in a reduction in standing waves and/or reflective notching (nonuniform linewidths due to reflections off the substrate). In addition, it can provide increased visual contrast at the patterned resist inspection stage. A variation on the visual contrast improvement involves the use of a dye which fluoresces, allowing for more precise resist metrology. The deposition and growth processes used here result in large oxide and polycrystalline silicon steps with high aspect ratios. Processes such as LOCOS which allow less severe topography, are inherently radiation soft and cannot be used on our fabrication process. The resulting steep sidewalls make metal coverage and etch significantly more difficult. Thus, the glass layer which isolates metal conductors from oxide steps is smoothed with either a thermal reflow or a plasma etch of a partially planarized coating to reduce the aspect ratio of the step. This results in metal coverage with a 45{degrees} angle at each step, which causes severe notching. This paper reports on an attempt to develop a resist which would eliminate this notching problem. Although the addition of unbleachable dye to photoresist for the control of notching is well established, most of the dyes used have one or more serious shortcomings, such as a poor match of the absorption spectrum with the exposure spectrum or low solubility in resist. Severe notching requires the use of a resist dye with optimized physical and spectroscopic properties to allow high optical absorbance to be achieved without the onset of other problems such as particulate formation or changes in thermal properties.

• OSTI ID: 5045341
• Journal Information: Journal of the Electrochemical Society; (United States), Journal Name: Journal of the Electrochemical Society; (United States) Vol. 136:1; ISSN 0013-4651; ISSN JESOA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601 -- Other Materials-- Preparation & Manufacture
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
ABSORPTION SPECTRA
ANTIREFLECTION COATINGS
AROMATICS
CHEMISTRY
COATINGS
CURCUMIN
DYES
ELECTRIC CONDUCTIVITY
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
EQUIPMENT
ETHERS
GLASS
HYDROXY COMPOUNDS
KETONES
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHENOLS
PHOTOCHEMISTRY
PHOTORESISTORS
PHYSICAL PROPERTIES
POLYPHENOLS
RESISTORS
SEMICONDUCTOR DEVICES
SOLAR ABSORBERS
SOLAR EQUIPMENT
SPECTRA
SPECTRALLY SELECTIVE SURFACES
SURFACES