TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal ions consist of copper ion, indium ion, gallium ion and selenium ion to form CIGS particles, and consist of copper ion, zinc ion and tin ion and sulfur and/or selenium ions to form CZTS particles. The CIGS particles have a structure of formula (CuInxGaySez).x = 0.74 plus minus 0.04;y = 0.165 plus minus 0.035; andz = 1.73 plus minus 0.13.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The first solution comprises water, first alkane and a first surfactant to form reverse micelles. The second solution comprises water, second alkane and a second surfactant to form reverse micelles. The first alkane and second alkane are cyclohexane. The first and second solution further contains alcohol, preferably 1-hexanol. The reducing agent is hydrazine monohydrate. Preferred Method: The microwave irradiation is carried out at a power of 500-2000 W. The method comprises, after the microwave irradiation, performing a membrane separation step to purify the solution containing the particles by dialysis. EXAMPLE - 8 ml of Triton-X 100 (RTM: Nonionic surfactant), 8.2 ml of 1-hexanol and 38 ml of cyclohexane were mixed. An aqueous solution containing copper chloride (54 mg), indium chloride (71 mg), gallium chloride (14 mg), selenious acid (103 mg) and deionized water (0.8 ml) were added to give solution (S1) and was stirred until stabilization at room temperature. 8.4 ml of Triton-X 100 (RTM: Nonionic surfactant), 8.2 ml of 1-hexanol, 38 ml of cyclohexane and 0.8 ml of hydrazine monohydrate were mixed to obtain a second solution (S2). The second solution (S2) was added dropwise to the first solution (S1). The first solution was stirred during the dropwise addition of the solution S2 to obtain a third solution (S3).The S3 solution was allowed under vigorous stirring at room temperature for 5 minutes so as to reduce metal ions present in the solution. Reducing agent was introduced excess relative to the ions present in solution. Copper, gallium, indium and selenium were reduced. The S3 solution was subjected to microwave irradiation for 1 minute and was destabilized by addition of ethanol (250 ml) to obtain CIGS particles.