ISSN:
0887-624X
Keywords:
chemical amplification
;
photoresist
;
poly(p-hydroxystyrene)
;
photocrosslinking
;
carbocationic
;
radiation-sensitive
;
crosslinker
;
triarylsulfonium salt
;
thin-film chemistry
;
UV
;
E-beam
;
x-ray
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
New resist systems based on acid-catalyzed, electrophilic aromatic substitution are described. These new resists show high sensitivity to deep UV and E-beam radiation with values approaching 2 mJ/cm2 and 2 μC/cm2, respectively. The resists are based on a three component system consisting of poly(4-hydroxystyrene), a polyfunctional, low molecular weight, latent electrophile, and a photoactive onium salt used as an acid generator. Irradiation of the resist film produces a latent image of acid dispersed in the matrix. During the postbaking step the photo-generated acid reacts with the latent polyfunctional electrophile and releases a reactive carbocationic intermediate with concomitant liberation of acetic acid. The carbocationic intermediate then reacts with neighboring phenolic moieties in a crosslinking reaction. The substitution reaction liberates a proton, making the process catalytic in nature, thus incorporating the concept of chemical amplification. These highly sensitive materials can be used as nonswelling negative multipurpose resists that function in deep-UV, x-ray or E-beam modes. © 1993 John Wiley & Sons, Inc.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1993.080310101