Poly(siloxane)-Based Chemically Amplified Resist Convertible into Silicate Glass

Abstract

A novel poly(siloxane)-based chemically amplified resist has been developed. The polymer is a glass precursor, and it can be converted to silicate glass through merely a lithographic procedure. The developed resist has a high sensitivity of 1.3 µC/cm2 and a high resolution of 0.1 µm lines and spaces. Simple and highly selective etching processes using the silicate glass mask obtained from this resist system have been proposed, which is substantiated in the bilevel resist process and tungsten-etching process.

Direct e-beam lithography of PDMS

“…It has a unique combination of properties including excellent thermal and chemical stability and non-toxicity making it an attractive material for use in many fields of science, especially in biomedical research [1]. Its sensitivity to electron radiation [2] has lead to its use as a resist for subsequent substrate patterning [3] albeit generally in a modified form [4][5][6]. Here we analyze the effects of exposing liquid PDMS to electron radiation over a large range of doses on the resulting elastic modulus and topography.…”

Demonstration of a Directly Photopatternable Spin-On-Glass Based on Hydrogen Silsesquioxane and Photobase Generators

“…The low molecular weight of this byproduct and the incorporation of oxygen through the introduction of new Si−O−Si linkages means that, in theory, the cure process results in a small weight gain. This reaction is in contrast to other chemically amplified cure systems where the loss of large bulky leaving groups results in a considerable weight loss during the conversion step. − …”

“…This reaction is in contrast to other chemically amplified cure systems where the loss of large bulky leaving groups results in a considerable weight loss during the conversion step. [20][21][22] To prepare and test these new photopatternable spinon-glass compositions, a PBG was added to a 25 wt % solution of hydrogen silsesquioxane in MIBK such that a PBG concentration of 0.1 to 7 wt % relative to the weight of the inorganic polymer was obtained. The solutions were filtered through a 0.45-µm filter onto the surface of a silicon wafer and spin coated at a speed of 1500 rpm to give films with a thickness of ∼1 µm (the silicon wafers utilized in the coating process were used as received from the manufacturer and were not surface treated).…”

“…The oxidative nature of both the photo and thermal cure processes results in a theoretical weight gain in the film during processing, thus eliminating the film shrinkage observed in other photopatternable spin-on-glass compositions that are based on bulky leaving groups and photoacid chemistries. 20,21…”

Acid-amplifying polymers: synthesis, characterization, and application to environmentally stable chemical amplification positive (ESCAP) resists

“…One of the most common combinations is an acid-reactive polymer with a photoacid generator (PAG). [1][2][3][4][5] PAGs photodecompose to generate acid species that catalyse the polymer reactions, resulting in signicant changes in the solubility of the polymers. The photosensitivity of such a system could be higher than that of a system that only includes a photoreactive polymer.…”