The present invention aims to provide a method by which fluorine-containing sulfide compounds, particularly sulfide compounds that contain hydrogen and fluorine, can be produced in a simple, low-cost and industrial manner. Provided is a method of producing a fluorine-containing sulfide compound represented by the following formula (2):

(F).sub.n-A.sup.3-S-A.sup.4-(F).sub.m(2)

(wherein A.sup.3 and A.sup.4 are independently an optionally substituted hydrocarbyl group with a carbon number of 1 to 3; n and m represent the numbers of fluorine atoms binding to A.sup.3 and A.sup.4, with n+m=1 to 13 being satisfied), comprising reacting a chlorine-containing sulfide compound represented by the following formula (1):

(Cl).sub.n-A.sup.1-S-A.sup.2-(Cl).sub.m(1)

(wherein A.sup.1 and A.sup.2 are independently an optionally substituted hydrocarbyl group with a carbon number of 1 to 3; n and m represent the numbers of chlorine atoms binding to A.sup.1 and A.sup.2, with n+m=1 to 13 being satisfied) and a fluorinating agent.

The present invention provides a compound represented by formula (I) wherein symbols in the formula are as defined in the specification.

##STR00001##

The present invention provides a compound represented by formula (I) wherein symbols in the formula are as defined in the specification.

##STR00001##

A method of making CF.sub.3CH.sub.2SH, comprising a step of reacting CF.sub.3CH.sub.2X, wherein X is halide or tosylate, with MSH, where M is an alkali metal such as Na or K, to yield CF.sub.3CH.sub.2SH.

A method of making CF.sub.3CH.sub.2SH, comprising a step of reacting CF.sub.3CH.sub.2X, wherein X is halide or tosylate, with MSH, where M is an alkali metal such as Na or K, to yield CF.sub.3CH.sub.2SH.

A photoacid generator compound having formula (I):

##STR00001## wherein, in formula (I), groups and variables are the same as described in the specification.

A photoacid generator compound having formula (I):

##STR00001## wherein, in formula (I), groups and variables are the same as described in the specification.

A method of making CF.sub.3CH.sub.2SH, comprising a step of reacting CF.sub.3CH.sub.2X, wherein X is halide or tosylate, with MSH, where M is an alkali metal such as Na or K, to yield CF.sub.3CH.sub.2SH.

A method of making CF.sub.3CH.sub.2SH, comprising a step of reacting CF.sub.3CH.sub.2X, wherein X is halide or tosylate, with MSH, where M is an alkali metal such as Na or K, to yield CF.sub.3CH.sub.2SH.

Disclosed are sulfur-containing compounds for plasma etching channel holes, gate trenches, staircase contacts, capacitor holes, contact holes, etc., in Si-containing layers on a substrate and plasma etching methods of using the same. The plasma etching compounds may provide improved selectivity between the Si-containing layers and mask material, less damage to channel region, a straight vertical profile, and reduced bowing in pattern high aspect ratio structures.