| 摘要 |
1,273,197. Semi-conductor devices. INTERNATIONAL BUSINESS MACHINES CORP. 10 Oct., 1969 [25 Oct., 1968], No. 49762/69. Heading H1K. [Also in Division C7] A method of applying a surface coating of dielectric material to a semi-conductor device comprises R.F. sputtering the dielectric material, such as silicon dioxide, on to the surface of the device, which has previously been coated with a layer of phosphosilicate glass, using such a target purity and power density and substrate temperature that the charge on the surface of the device is maintained during deposition at less than 5 x 10<SP>12</SP> electronic charges per square centimetre. The thickness of the phosphosilicate glass layer is in the range 650-3000 Š, the target positive impurity ion density is less than 1 x 10<SP>18</SP> ions per c.c. and the R.F. power density is between 10 and 25 watts/square inch, the semi-conductor surface being maintained below 250‹ C. during deposition. The dielectric layer is applied in a conventional R.F. sputtering apparatus by sputtering in the floating mode wherein the substrate is electrically isolated from the anode by a quartz spacer. The phosphosilicate glass is applied by the open-tube diffusion method. |
