introduced to the reaction zone 215 to produce carbonitride mixture particles containing a plurality of metals the carbonitride mixture particles may be oxidized to oxycarbonitride mixture particles at the reaction zone 216 by introducing the carrier gas and the oxygen source thereto in fig2 laser lights are emitted from the respective lasers to the reaction zone 215 and the reaction zone 216 in another embodiment laser light emitted from a laser may be split into two laser lights in such embodiments attenuators are preferably provided after the splitter to control the powers individually fig3 schematically illustrates an embodiment in which laser light emitted from a single laser is split in fig3 the numeral 301 indicates a laser 302 a laser beam splitter 303 a reflecting mirror 304 a first attenuator 305 a second attenuator 306 a first condensing lens 307 a second condensing lens 308 a chamber 309 a first carrier gas inlet 310 a metal compound material inlet 311 a carbon source inlet 312 a nitrogen source inlet 313 a reaction gas inlet 314 a second carrier gas inlet 315 an oxygen source inlet 316 a reactive gas inlet 317 a product outlet 318 a first reaction zone and 319 a second reaction zone when two reaction zones are provided the oxygen source.