Abstract:Photoresists have been widely used as patterning materials for electronic devices such as displays and semiconductors. Understanding pattern formation mechanisms is essential for the efficient development of resist materials. In particular, the dissolution mechanism of resist materials is an important process in pattern formation. In this study, the dissolution mechanisms of negative-type resists for display manufacture were investigated using a quartz crystal microbalance (QCM) method. The changes in frequenc… Show more
“…The increase in impedance change is considered to indicate the increase in polymer concentration near the polymer film surface because the observed dissolution kinetics are typical for the dissolution in Case II diffusion. [25][26][27][28][29] The maximum impedance change decreased with increasing protection ratios. This decrease indicates the decrease in solubility due to the increase in protection ratio.…”
A 0.26 M tetramethylammonium hydroxide (TMAH) aqueous solution has been used as a standard developer for manufacturing semiconductor devices. Alternative developers have recently attracted much attention because the 0.26 M TMAH developer may be approaching its performance limit. In this study, we measured the dissolution and swelling behavior of resist polymers in tetraalkylammonium hydroxide (TAAH) aqueous solutions using a quartz crystal microbalance method to clarify the effects of the alkyl chain length of TAAH. The resist polymer was poly(4-hydroxystyrene), whose hydroxyl groups were partially protected with t-butoxycarbonyl groups. When the alkyl chain length of TAAH was increased from two (ethyl) to three (propyl), the dissolution mode markedly changed. The dissolution mode did not depend on the polymer polarity. The change of the dissolution mode is probably caused by the size effect of TAAH, considering the independence of polymer polarity and the discrete change of the dissolution mode.
“…The increase in impedance change is considered to indicate the increase in polymer concentration near the polymer film surface because the observed dissolution kinetics are typical for the dissolution in Case II diffusion. [25][26][27][28][29] The maximum impedance change decreased with increasing protection ratios. This decrease indicates the decrease in solubility due to the increase in protection ratio.…”
A 0.26 M tetramethylammonium hydroxide (TMAH) aqueous solution has been used as a standard developer for manufacturing semiconductor devices. Alternative developers have recently attracted much attention because the 0.26 M TMAH developer may be approaching its performance limit. In this study, we measured the dissolution and swelling behavior of resist polymers in tetraalkylammonium hydroxide (TAAH) aqueous solutions using a quartz crystal microbalance method to clarify the effects of the alkyl chain length of TAAH. The resist polymer was poly(4-hydroxystyrene), whose hydroxyl groups were partially protected with t-butoxycarbonyl groups. When the alkyl chain length of TAAH was increased from two (ethyl) to three (propyl), the dissolution mode markedly changed. The dissolution mode did not depend on the polymer polarity. The change of the dissolution mode is probably caused by the size effect of TAAH, considering the independence of polymer polarity and the discrete change of the dissolution mode.
“…It is also important to understand the fundamentals of development and rinse processes to improve the development processes. [2][3][4] Thus, in this study, we measured the dissolution and swelling behavior of tetraalkylammonium hydroxide (TAAH) aqueous solutions in resist polymers using a quartz crystal microbalance (QCM) method. The resist polymer was poly(4-hydroxystyrene) (PHS), the hydroxyl groups of which were partially protected with t-butoxycarbonyl groups.…”
Recently chemically amplified resists are approaching their performance limits due to the fixed development process. In this study, the dissolution, swelling, and impedance change of resist polymers were measured by a development analyzer with a quartz crystal microbalance method. The resist polymer was poly(4-hydroxystyrene) (PHS), the hydroxyl groups of which were partially protected with t-butoxycarbonyl groups. The alkyl chain lengths of tetraalkylammonium hydroxide were varying from methyl to pentyl groups. When the alkyl chain length of TAAH increased from two to three, the dissolution mode markedly changed.
“…The development processes of resist films have been widely investigated by various methods, such as visible and infrared reflectance spectroscopy, 13) a quartz crystal microbalance (QCM) method, [13][14][15][16][17][18][19][20] and high-speed atomic force microscopy (AFM). 21) The dissolution is divided into three steps: [13][14][15][16][17][18][19][20] the diffusion of solvent molecules into the polymer bulk and subsequent swelling, the reaction between the polymer and the solvent molecules, and the diffusion of the polymer chain into the solvent bulk.…”
The dissolution (including the formation of a transient swelling layer) of a resist polymer is key to realizing ultrafine patterning. However, the details of the dissolution of resist polymers remain unclarified. In this study, the swelling and dissolution kinetics of poly(4-hydroxystyrene) (PHS) films in tetramethylammonium hydroxide (TMAH) and tetrabutylammonium hydroxide (TBAH) aqueous solutions were investigated by a quartz crystal microbalance (QCM) method. PHS is a typical backbone polymer (a dissolution agent) of chemically amplified resists. The swelling and dissolution kinetics of PHS were observed by changing the protection ratio of the hydroxyl groups of PHS and the alkaline concentration in developers. Not only the dissolution rate but also the mode of dissolution depended on the molecular structure of tetraalkylammonium cations. For polymer matrices with strong hydrogen bond networks such as PHS, the penetration of tetrabutylammonium cations is considered to be strongly suppressed by their long alkyl chains.
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.