Abstract: A wafer processing method of dividing a wafer along a plurality of crossing streets formed on the wafer to obtain individual chips. The wafer processing method includes a modified layer forming step of applying a laser beam having a transmission wavelength to the wafer along each street to thereby form a modified layer inside the wafer and a dividing step of applying an external force to the wafer to thereby divide the wafer into the individual chips along each street with the modified layer functioning as a division start point. In the modified layer forming step, the modified layer is formed at each intersection of the crossing streets at a height where cracking can be avoided on the corner edges of each chip obtained by dividing the wafer.

Abstract: In a method for producing a silicon single by pulling the silicon single crystal from a silicon melt contained in a crucible, a magnetic field is applied to the silicon melt in a radial direction of the silicon single crystal, and a vertical level of a center of the magnetic field relative to a surface of the silicon melt is controlled such that a thermal gradient in an axial direction of the crystal is maintained at a constant value in respective portions along a radial direction of the silicon single crystal.

Abstract: To provide an active electronic device which is formed from a carbon nanotube and which excels in high frequency operation and an electronic apparatus using the active electronic device. Provided are the active electronic device including: a carbon nanotube (1); a first electrode (S) connected to one end of the carbon nanotube; a second electrode (D) connected to the other end of the carbon nanotube; and a third electrode (G) facing the carbon nanotube (1) to irradiate the carbon nanotube (1) with electromagnetic waves, in which the amount of current flowing into the carbon nanotube (1) is changed by electromagnetic waves, at least high frequency electromagnetic waves, radiated from the third electrode onto the carbon nanotube (1), and the electronic apparatus using the active electronic device.