NOVELTY - Silicon powder containing metal impurity is fed into container (I), and the metal impurity is dissolved by adding mixed solution (A) containing hydrochloric acid and hydrogen-peroxide solution. Then, the silicon powder is added to container (II), and mixed solution (B) comprising hydrochloric acid, nitric acid and hydrofluoric acid is added. The generated silicon tetrafluoride is discharged, solution (B) is heat-evaporated, mixed solution (B) is newly added to metal deposit and heated. Then, the concentration of metal impurity extracted from mixed solution (B) is measured.    USE - Analysis of metal impurity in silicon powder used for solar cell.    ADVANTAGE - The method efficiently and accurately analyzes impurity concentration in surface and inside portion of silicon powder by inductively coupled plasma atomic emission spectrometry.    DETAILED DESCRIPTION - Silicon powder containing metal impurity is fed into a container (I), and the metal impurity adhered to surface of silicon powder is dissolved by adding mixed solution (A) containing hydrochloric acid and hydrogen-peroxide solution or hydrofluoric acid and hydrogen-peroxide solution to silicon powder and allowing to stand still for predetermined time. Then, the silicon powder is picked out from the container (I) and added to a container (II), and a mixed solution (B) comprising hydrochloric acid, nitric acid and hydrofluoric acid is added to silicon powder in container (II). The generated silicon tetrafluoride is released out from the container (II), and the metal impurity is deposited by evaporating mixed solution (B). The mixed solution (B) is newly added to the precipitated metal impurity, and heat-dissolution process is carried out to dissolve precipitated metal impurity. Then, the concentration of metal impurity extracted from the mixed solution (B) is measured by metal-analysis process.    DESCRIPTION OF DRAWING(S) - The drawing shows a flowchart of analysis of metal impurity in silicon powder. (Drawing includes non-English language text)