| 摘要 |
1284109 Printed circuits; resistors WESTERN ELECTRIC CO Inc 2 Dec 1969 [6 Dec 1968] 58685/69 Headings HlR and HIS A method of making a thin-film circuit comprises the steps of depositing a resistive layer on to a substrate, and then a conductive layer on to the resistive layer, removing an area of the conductive layer, by masking techniques, which includes the area of the required resistor, and finally removing part of both layers, again by masking techniques, to define the complete circuit pattern, including the resistor. The masking techniques used may consist of applying a photo-resist and then etching unwanted parts. The substrate may be made of glass, fused silica, glazed or unglazed ceramic, quartz or sapphire. The conductive layer may consist of two or more layers, for example, a chromium, nichrome or titanium layer followed by a gold or palladium layer. The resistive layer may be made of tantalum, or compounds thereof. Anodization may be used to increase the value of the resistor, after the circuit has been completed. This method may also be used to form capacitative components. |
