Abstract: A plasma treatment method comprising exhausting a process chamber so as to decompress the process chamber, mounting a wafer on a suscepter, supplying a process gas to the wafer through a shower electrode, applying high frequency power, which has a first frequency f.sub.1 lower than an inherent lower ion transit frequencies of the process gas, to the suscepter, and applying high frequency power, which has a second frequency f.sub.2 higher than an inherent upper ion transit frequencies of the process gas, whereby a plasma is generated in the process chamber and activated species influence the wafer.

Abstract: A semiconductor device having lead terminals bent in a J-shape is disclosed. A radiating plate having a recess formed on an outer peripheral portion thereof is exposed to a lower face of a resin member and free ends of outer portions of the lead terminals are positioned in the recess of the radiating plate. The free ends of the outer portions of the lead terminals and the recess of the radiating plate are isolated from each other by projections of the resin member. Since the radiating plate is exposed to the lower face of the resin member, the heat radiating property is high whereas the radiating plate and the lead terminals are not short-circuited to each other at all.

Abstract: A plasma processing apparatus comprises a chamber, and an upper electrode and a lower electrode, parallelly provided in the chamber to oppose each other at a predetermined interval, for defining a plasma generation region between the electrodes. An object to be processed is mounted on the lower electrode. RF powers are supplied to the electrodes, so that a plasma generates between the electrodes, thereby performing a plasma process with respect to the object to be processed. A cylindrical ground electrode is provided around the plasma generation region in the chamber, for enclosing the plasma in the plasma generation region, and has a plurality of through holes for passing a process gas.

Abstract: A high frequency switching circuitry comprising the following elements. At least one input signal terminal is provided into which an input signal is inputted. An output signal terminal is also provided, from which an output signal is outputted. A first resistive switching circuit is connected between the input signal terminal and a first node. The first resistive switching circuit has first and second signal transmission channels having first and second resistances. The second resistance of the second channel is much higher than the first resistance of the first channel. The first resistive switching circuit switches the first and second signal transmission channels. A first switching element is connected between the first node and the output terminal. A second switching element is connected in series between the first node and a ground line.

Abstract: A plasma treatment apparatus comprising a chamber earthed, a vacuum pump for exhausting the chamber, a suscepter on which a wafer is mounted, a shower electrode arranged in the chamber, opposing to the suscepter, a unit for supplying plasma generating gas to the wafer on the suscepter through the shower electrode, a first radio frequency power source for adding radio frequency voltage, which has a first frequency f.sub.1, to both of the suscepter and the shower electrode, a second radio frequency power source for adding radio frequency voltage, which has a second frequency f.sub.2 higher than the first frequency f.sub.1, at least to one of the suscepter and the shower electrode, a transformer whose primary side is connected to the first radio frequency power source and whose secondary side to first and second electrodes, and a low pass filter arranged in a circuit on the secondary side of the transformer, and serving to allow radio frequency voltage, which has the first frequency f.sub.

Abstract: The molded type semiconductor device has a semiconductor chip mounted and molded on a lead frame. The device includes a stub which has an open end at a portion of the lead frame and which is connected to a ground electrode of the semiconductor chip, and a mold resin which molds the stub together with the semiconductor chip. The stub has a length that is a 1/4 wavelength of a signal wavelength used in the device. The stub is formed in a zigzag form or a spiral form. Due to such stub, the satisfactory grounding is ensured to accomplish a simple molded type structure and to improve circuit characteristics.