| 摘要 |
PURPOSE:To obtain a polycrystal optical material contg. no foam and inclusion at a good yield by supplying compds. of two kinds of constituting elements constituting a polycrystal optical material together with gaseous He to a reaction furnace kept under and at low pressure and low temp. to effect the reaction and annealing the formed polycrystal optical material under specific pressure and temp. conditions. CONSTITUTION:An org. compd. of Zn which is one element [e.g.; (CH3)2Zn] and a compd. of the other element (e.g.; H2S) are supplied respectively with gaseous He as a carrier gas into a reaction furnace to effect the reaction in the case of producing ZnS as the above-described optical material. The temp. in the reaction furnace in this stage is set within the range of 300-500 deg.C and the pressure within 10<-3>-10<-1>Torr and ZnS is deposited in a chemical vapor phase on a substrate. The substrate is then heated to 700-750 deg.C higher by the above-described reaction temp. in the high-temp. gaseous He atmosphere under 10<-3>-10<-1>Torr by which the optical material is annealed. As a result, the ZnS, i.e., the optical material having a small grain size contg. no foam is obtd. at a good yield. |
