摘要:
A semiconductor device of the MOS construction such that a gate oxide film of the device has a gate area in the range of from 5 to 15 mm² and a thickness in the range of from 15 to 40 nm and the oxide film dielectric breakdown voltage is not less than 8 MV/cm when a gate current caused to flow in response to application of a direct-current voltage between a phosphorus-doped polysilicon electrode formed on the oxide film and a silicon single crystal substrate increases past 1µ A/mm² as current density is obtained by using a silicon wafer substrate having an oxygen concentration of not more than 1 x 10¹⁸ atoms/cm³.
摘要:
A single crystal pulling apparatus based on Czochralski technique having a conduit for continuously supplying granular polycrystal material to the crucible and a vertical purge tube (7) suspended centrally into the heating chamber, wherein the purge tube is vertically shiftable; a heat shield ring (8) is connected to the lower end of the purge tube, and a cylindrical quartz partition ring (9) made of a quartz glass containing no bubbles is held vertically by the heat shield ring in a manner such that the lower end of the quartz partition ring comes substantially lower than the lower end of the purge tube so that, by being dipped in the polycrystal melt, the partition ring isolates the interior surface of the melt from the exterior surface of the melt, over which latter the granular polycrystal material is poured.
摘要:
An apparatus for continuously supplying granular polycrystal silicon to a crucible of a semiconductor single crystal pulling apparatus, comprising a funnel-shaped tank having a relatively large capacity, a main hopper having a relatively small capacity and weight, a subhopper having an intermediate capacity and weight and providing a passage from said tank to said main hopper, and a weight sensor for detecting the weight of the main hopper, wherein the overall weight of the main hopper is measured to obtain the flow rate (supply rate) of the granular polycrystal silicon.
摘要:
In a method for heat process of silicon, a single crystal silicon produced by the Czochralski process is thermally processed at a low temperature ranging from 400 °C to 550 C . Outside this temperature range, the oxygen precipitate is not adequate. The result is that a predetermined oxygen precipitate can be obtained uniformly in the crystal growth direction without any reduction especially at the crystal bottom part. The resulting silicon is particularly suitable for manufacture of LSI.
摘要:
A novel device for producing a single crystal by the CZ or MCZ method is provided, which comprising a crucible for containing silicon melt therein, a wire reel and a wire for pulling a single crystal, a motor and a rotation shaft for rotating the crucible, a speed change device being inserted between the motor and the rotation shaft, and, if necessary, a magnetic field generator, by which the magnetic field is applied to the melt. According to the device for producing a single crystal, the rotation accuracy of a crucible can be improved, so that the concentrations of impurities in the pulled single crystal can be highly precisely controlled.
摘要:
An equipment for producing silicon single crystals based on an MCZ method, which enables an operator to be protected from dangerous exposure to magnetic field without involving increase in the size of the silicon single crystal production equipment. In the silicon single crystal production equipment based on the MCZ method, a growth furnace control apparatus for control of a pulling apparatus is located away from the pulling apparatus by a predetermined distance so that the intensity of magnetic field immediately close to the growth furnace control apparatus can become 300 gausses or less. A monitoring camera for observing the growing condition of the silicon single crystal is mounted to a window 5a of a growth furnace to be operatively connected to a monitor of the growth furnace control apparatus and to cause the growth furnace control apparatus to control the pulling apparatus on a remote control basis. In an experimental example, an accumulated magnetic field exposure value immediately close to the growth furnace control apparatus can be suppressed to less than 30% of its allowable maximum value and therefore the operator can continuously work highly safely.