Method for processing waste gas exhausted from chemical vapor and deposition equipment

A method of processing waste gas exhausted from chemical vapor deposition equipment, which comprises:

• a) contacting a waste gas containing viscous substances with a filtering aid agent;
• b) passing the waste gas containing said viscous substances exhausted from the chemical vapor deposition equipment, and which has been contacted with said filtering aid agent, through a filtering and dust collecting unit, whereby said viscous substances are condensed with said filtering aid agent on said filtering and dust collecting unit;
• and
• c) removing the condensed matter from the surface of the filter, thereby preventing clogging thereof;
• and
• wherein said viscous substances are selected from the group consisting of lower alcohols, lower aldehydes, silicon compounds, boron compounds and phosphorus compounds which are by-products of chemical vapor deposition;
• and
• wherein said filtering aid agent is selected from the group consisting of perlite and diatomaceous earth having a particle size of from about 5 to 40 .mu.m.