Abstract: A technique for readily concealing confidential information contained in document data can be offered. An information processing apparatus according to an embodiment includes: a document data acquisition part configured to acquire first document data including sentences that contain character information; a sentence separation part configured to separate the first document data into sentences; a concealment target determination part configured to determine whether or not each of the sentences included in the first document data is a concealment target, in accordance with a preset rule; a concealment processing part configured to execute a concealment process upon the sentence when the sentence is determined to be a concealment target; and an output part configured to output second document data including a sentence obtained by executing the concealment process by the concealment processing part.

Abstract: A polysilicon film which realizes an excellent ohmic contact is obtained. A board 4 to which a silicon substrate 3 is fixed is disposed within a chamber 1. An SiH.sub.4 gas, an N.sub.2 gas, a TEOS gas and an anhydrous HF gas are introduced into the chamber 1, through valves 8a, 8b, 8c and 8d, respectively. By means of a pump 7 through a valve 6, the air inside the chamber 1 is exhausted. The chamber 1 is heated up by a heater 2. First, the N.sub.2 gas, the TEOS gas and the anhydrous HF gas are introduced into the chamber 1, to remove a silicon natural oxidation film 34 which is formed on the silicon substrate 3. Next, after exhausting the air inside the chamber 1, the SiH.sub.4 and the N.sub.2 gas are introduced into the chamber 1, to form a polysilicon film 35 on the silicon substrate 3.

Abstract: A vacuum CVD apparatus including a reaction chamber into which a fluorine-containing compound gas and a carrier gas are introduced for cleaning. The fluorine-containing compound gas reacts with the matter deposited on the inner surface of the reaction chamber to gasify and remove the matter, preventing contamination of a semiconductor wafer later placed in the reaction chamber. Thus, it is possible to achieve high reliability of VSLIs produced in the reaction chamber.

Abstract: In a semiconductor device manufacturing apparatus for forming silicon oxide films on semiconductor wafers by reduced-pressure CVD, anhydrous HF gas and an interhalogen compound gas are introduced along with a carrier gas to a reaction chamber or a vacuum evacuation pipe. The anhydrous HF gas and the interhalogen compound gas react with deposits adhering to an inner wall of the reaction chamber and the vacuum evacuation pipe so that the deposits are decomposed into gases and removed. Particles attributable to the deposits are prevented from adhering to the semiconductor wafers.

Abstract: A vacuum CVD apparatus including a reaction chamber into which a fluorine-containing compound gas and a carrier gas are introduced for cleaning. The fluorine-containing compound gas reacts with the matter deposited on the inner surface of the reaction chamber to gasify and remove the matter, preventing contamination of a semiconductor wafer later placed in the reaction chamber. Thus, it is possible to achieve high reliability of VSLIs produced in the reaction chamber.

Abstract: A reduced pressure processing apparatus includes a processing vessel for performing predetermined processing to an object to be processed in a reduced pressure atmosphere, an exhaust mechanism, including a main exhaust system having a relatively high exhaust pressure and a sub-exhaust system having a relatively low exhaust pressure, for evacuating the processing vessel, and an oxygen gas concentration sensor for detecting an oxygen gas concentration in the processing vessel during exhaust performed by the sub-exhaust system. The oxygen gas concentration in the processing vessel is detected while the processing vessel is evacuated with a relatively low exhaust pressure. It is determined whether leakage is present or absent by confirming a detection value is a predetermined value or less within a predetermined period of time. When leakage is absent, the processing vessel is evacuated with the relatively high exhaust pressure.