Abstract:
Ultrashort pulse laser processing bores, welds or cuts objects (work pieces) by converging ultrashort laser pulses by a lens on the objects (work pieces) positioned at the focus and heating small spots or narrow lines on the objects (work pieces). Shortage of a focal depth of the lens prevents the ultrashort pulse laser processing from positioning the object (a work piece) and forming a deep, constant-diameter cylindrical hole. Z-parameter is defined to be Z=2fc&Dgr;t/&Dgr;i2, where &Dgr;t is a FWHM pulse width of the ultrashort pulse laser, &Dgr;i is a FWHM beam diameter of the ultrashort pulse, f is a focal length of the lens and c is the light velocity in vacuum. Selection of an optical system including a diffraction-type lens which gives the Z-parameter less than 1 (Z
Abstract:
Ultrashort pulse laser processing bores, welds or cuts objects (work pieces) by converging ultrashort laser pulses by a lens on the objects (work pieces) positioned at the focus and heating small spots or narrow lines on the objects (work pieces). Shortage of a focal depth of the lens prevents the ultrashort pulse laser processing from positioning the object (a work piece) and forming a deep, constant-diameter cylindrical hole. Z-parameter is defined to be Z=2fc&Dgr;t/&Dgr;i2, where &Dgr;t is a FWHM pulse width of the ultrashort pulse laser, &Dgr;i is a FWHM beam diameter of the ultrashort pulse, f is a focal length of the lens and c is the light velocity in vacuum. Selection of an optical system including a diffraction-type lens which gives the Z-parameter less than 1 (Z
Abstract:
Ultrashort pulse laser processing bores, welds or cuts objects (work pieces) by converging ultrashort laser pulses by a lens on the objects (work pieces) positioned at the focus and heating small spots or narrow lines on the objects (work pieces). Shortage of a focal depth of the lens prevents the ultrashort pulse laser processing from positioning the object (a work piece) and forming a deep, constant-diameter cylindrical hole. Z-parameter is defined to be Z=2fc&Dgr;t/&Dgr;i2, where &Dgr;t is a FWHM pulse width of the ultrashort pulse laser, &Dgr;i is a FWHM beam diameter of the ultrashort pulse, f is a focal length of the lens and c is the light velocity in vacuum. Selection of an optical system including a diffraction-type lens which gives the Z-parameter less than 1 (Z
Abstract:
In order to easily control the laser pulse width and perform high-precision processing, the method for processing a material by laser ablation according to the present invention is characterized in that the material having a region of which a double logarithmic chart shows a linearly-shaped line with a gradient of not more than 0.5, when a relationship between laser pulse width and ablation threshold is represented in the logarithmic chart with a laser pulse width in picosecond plotted along the horizontal axis and an ablation threshold in J/cm 2 plotted along the vertical axis, is processed by the pulsed laser beam having the laser pulse width within the region.
Abstract:
Ultrashort pulse laser processing bores, welds or cuts objects (work pieces) by converging ultrashort laser pulses by a lens on the objects (work pieces) positioned at the focus and heating small spots or narrow lines on the objects (work pieces). Shortage of a focal depth of the lens prevents the ultrashort pulse laser processing from positioning the object (a work piece) and forming a deep, constant-diameter cylindrical hole. Z-parameter is defined to be Z = 2fc t/ i , where t is a FWHM pulse width of the ultrashort pulse laser, i is a FWHM beam diameter of the ultrashort pulse, f is a focal length of the lens and c is the light velocity in vacuum. Selection of an optical system including a diffraction-type lens which gives the Z-parameter less than 1 (Z
Abstract:
There is provided a semiconductor device including: a gate electrode (2); a channel layer (7) arranged in a region directly below or directly above the gate electrode (2); a source electrode (5) and a drain electrode (6) arranged to be in contact with the channel layer (7); and a first insulating layer (3) arranged between the gate electrode (2) and the channel layer (7), the channel layer (7) including a first oxide semiconductor, at least one of the source electrode (5) and the drain electrode (6) including a second oxide semiconductor, and the first oxide semiconductor and the second oxide semiconductor containing indium, tungsten and zinc. There is also provided a method for manufacturing the semiconductor device.
Abstract:
There is provided an oxide sintered body including indium, tungsten and zinc, wherein the oxide sintered body includes a bixbite type crystal phase as a main component and has an apparent density of higher than 6.5 g/cm 3 and equal to or lower than 7.1 g/cm 3 , a content rate of tungsten to a total of indium, tungsten and zinc is higher than 1.2 atomic % and lower than 30 atomic %, and a content rate of zinc to the total of indium, tungsten and zinc is higher than 1.2 atomic % and lower than 30 atomic %. There are also provided a sputtering target including this oxide sintered body, and a semiconductor device (10) including an oxide semiconductor film (14) formed by a sputtering method by using the sputtering target.
Abstract:
There is provided an oxide sintered body including indium, tungsten, and at least one of zinc and tin, wherein the oxide sintered body includes, as a crystal phase, a complex oxide crystal phase including tungsten and at least one of zinc and tin. There is also provided a semiconductor device (10) including an oxide semiconductor film (14) formed by a sputtering method by using the oxide sintered body as a target.