| 摘要 |
1278898 Fluoride-doped zinc oxide RCA CORPORATION 12 May 1970 [12 May 1969] 22866/70 Heading C1A [Also in Division H1] Photoconductive zinc oxide is doped with a fluoride to give it a quenched luminescence characteristic during electrostatic charging thereof. In one embodiment, Fig. 1, pure zinc 12 is vaporized and swept by a stream of Ar or N 2 into heated reaction chamber 16 where it is mixed with two streams 34, 36, each stream being a mixture of O 2 and F 2 . The two streams are produced by mixing streams of O 2 and F 2 in a chamber 28. The fluorine-doped ZnO is extracted at 20, if required by suction. The stream of O 2 may be replaced by air whilst the stream of F 2 may be replaced by HF, NH 4 F or ZnF 2 . The amount of oxygen is controlled to give stoichiometric ZnO whilst the fluorine content is 10<SP>-5</SP> to I wt. per cent of the ZnO. In another embodiment, pure ZnO is moistened with a dilute aqueous solution of KF or NH 4 F and heated to at least 450‹ C. to diffuse fluoride ions into the oxide lattice. |
