Abstract: A semiconductor device includes a semiconductor body (1) having a semiconductor element with connection points (2, 3) which adjoins a surface (4) of the semiconductor body (1) and is laterally insulated and surrounded by a first depression (5) in the surface (4), which depression (5) is provided with a wall (6) and a bottom (7), while the surface (4) of the semiconductor body (1) and the wall (6) and bottom (7) of the depression (5) are covered with an insulating layer (8). The connection points (2, 3) are provided in the insulating layer (8) on the surface (4) of the semiconductor body (1) and are connected to conductor tracks (10, 11) which connect the connection points (2, 3) across a wall (6) to connection surfaces (12, 13) associated with the connection points (2, 3) and situated on the bottom (7). It is found in practice that, in the case of progressive miniaturization, the manufacture of such devices leads to rejects caused by short-circuits between connection surfaces (12, 13).

Abstract: A semiconductor device with a semiconductor body (1) is provided with a first and a second bipolar transistor (T1, T2, respectively) in a cascode configuration, in which the semiconductor body (1) comprises, in that order, a collector region (10) and a base region (11) of the first transistor (T1), a region (12) which forms both an emitter region of the first transistor (T1) and a collector region of the second transistor (T2), a space charge region (13), and a base region (14) and emitter region (15) of the second transistor (T2), while the regions form pn junctions with one another which extend parallel to a main surface (2) of the semiconductor body (1). The base region (14) and the emitter region (15) of the second transistor (T2) adjoin a main surface (3) of the semiconductor body (1).

Abstract: A master disc which is provided on one side with a reflective optical structure and a recording double-layer is exposed to a first laser beam which scans the optical structure and to a second laser beam which is controlled by the first beam, information bits in the form of bulges being formed in the recording layer due to exposure to the second beam, a metal skin being subsequently provided on the recording layer, in which metal skin the surface structure of the recording layer is copied and, finally, the matrix thus obtained being removed from the master disc.

Abstract: A master disc which is provided on one side with a reflective optical structure and a recording double-layer is exposed to a first laser beam which scans the optical structure and to a second laser beam which is controlled by the first beam, information bits in the form of bulges being formed in the recording layer due to exposure to the second beam, a metal skin being subsequently provided on the recording layer, in which metal skin the surface structure of the recording layer is copied and, finally, the matrix thus obtained being removed from the master disc.

Abstract: A record carrier is described for optically writing and reading information, which record carrier is provided with a pre-formed track. This track is formed by a ridge disposedon the substrate surface and the recording layer comprises a dye layer having such a thickness at the location of the ridge that a write beam can produce a maximum optical effect therein, the dye layer being thicker at locations outside the ridge.

Abstract: Erasable optical recording element according to FIG. 1 having a substrate 1 and a recording layer 4 which is provided thereon and which satisfies the formula (QSb).sub.100-x M.sub.x, wherein Q is the element Ga or In, M is a metal or chalcogenide element and x has the value 2-15, as well as a method of optically recording and erasing information in which under the influence of pulsated laser light amorphous info areas 10 are formed in the recording layer 4, which areas can be reverted by laser light to the crystalline phase and can be erased.

Abstract: According to the method a rotating recording element 23 (FIG. 3) having a crystalline recording layer 28 of the composition Q.sub.x Sb.sub.y Te.sub.z, wherein Q=In, Ga; X=34-44 at. %; y=51-62 at. %; Z=2-9 at. %; is exposed to a pulsated laser light spot 29 (FIG. ) in which amorphous information bits are formed which are read by means of weak laser light 30 and which can be erased in real time during one revolution of the element 23 by means of a laser light erasing spot 33 (FIG. 4) and be returned to the crystalline state.

Abstract: A method is provided for the optical recording of information in which an amorphous recording layer 4 having a composition according to formula (1) provided on a synthetic resin substrate (2) (FIG. 1) in a maximum layer thickness of 150 nm is exposed of infrared laser light having a wavelength of 750-900 nm and pulsed in accordance with the binary information to be recorded with a pulse time of at most 200 ns. A crystalline area 6 (bit) having maximum dimensions of a few micrometers is formed in the amorphous layer in the exposed places. As optical recording element is also provided for use in the method.

Abstract: A method of manufacturing a homogeneous, water-insoluble dye layer on a substrate is provided in which a solution of a cationic or anionic dye in an organic solvent is provided on the substrate, the solvent is removed and the resulting dye layer is treated with an aqueous solution of a salt in which the cation of the anionic dye is exchanged for the cation of the salt or is treated with a salt or acid in which the anion of the cationic dye is exchanged for the anion of the salt or acid. The invention also provides a substrate provided with water insoluble homogeneous dye layer.

Abstract: A method for the optical recording of information in which a recording layer 4 of In.sub.x Sb.sub.1-x, Ga.sub.x Sb.sub.1-x or (InSb).sub.y Se.sub.1-y, wherein 0.4.ltoreq.x.ltoreq.0.6 and 0.7.ltoreq.1.0, or mixtures thereof, provided on a synthetic resin substrate (2) (FIG. 1) in a maximum layer thickness of 150 nm is exposed to infrared laser light having a wavelength of 750-900 nm which is pulsated in accordance with the binary information to be recorded with a pulse time of at most 200 ns, a crystalline area 6 (bit) having maximum dimensions of a few micrometers being formed in the amorphous layer in the exposed places, as well as an optical recording element used in the method.

Abstract: An optical recording element having a recording layer which comprises an alkylpyrylium-squarylium dye, as well as novel alkylpyrylium-squarylium compounds.