(H01L21/311)

Semiconductor chemical etching method

Chemical etching of a semiconductor surface is carried out in an etching agent consisting of the following components: hydrofluoric acid (HF), nitric acid (HNO3) and acetic acid (CH3COOH) in ratio of 1:6:3.

Photoactivated composition for etching silicon nitride films

Invention relates to production of integrated microcircuits and other electronic devices which use a plenary manufacturing technique based on photolithographic processes. The photoactivated composition contains a polymer base and a photosensitive component. The polymer base is polymethyl methacrylate and the photosensitive component is ammonium fluoride. The composition further contains a protophilic reagent - α-naphthylamine and solvents - acetone and trifluoroacetic acid. Components are in the following ratio, wt %: polymethyl methacrylate - 11.8; ammonium fluoride - 4.7-7.1; α-naphthylamine - 18.3; acetone - 8.3-10.7; trifluoroacetic acid - 54.5. Use of the composition simplifies the technological process of obtaining photoetched pattern in a silicon layer, while excluding development, baking and wet chemical etching steps.

Method of protecting polyimide materials during etching

Method of protecting polyimide materials during etching involves a process for etching parts of the polyimide material with alkaline solutions. Before the etching process, the polyimide material is covered with a mixture of epoxy-urethane varnish with an oligoester acrylate additive, with the following ratio of components, wt %: epoxy-urethane varnish 93.7-95.2, oligoester acrylate 4.8-6.3. The part of the polyimide material which is not supposed to be etched is then protected with an insulating layer.