| 摘要 |
1,212,114. Semiconductor devices. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 6 Aug., 1968 [9 Aug., 1967], No. 37463/68. Heading H1K. [Also in Division C7] An N.T.C. resistor is made as a thin film of aluminium-doped silicon nitride on a substrate. The film may be shaped by etching or sandblasting to obtain the desired resistance value and may then be given superimposed Ni/Cr and Au films as electrodes. The resistor may be formed by reactive sputtering using a cathode which includes aluminium. Several masked substrates (of e.g. glass, ceramic, or mica) are placed on a rotatable anode (41) opposite a silicon-aluminium-faced cathode of the same size (a small cathode may be used if the rotational axis of the anode is offset). The cathode is liquid-cooled and is surrounded by an earthed protective ring (30). The chamber is provided with transparent loading windows (24) and is evacuated by floor ducts, the argon-nitrogen mixture for sputtering being fed into the space between the cathode and the protective ring. Cathode construction is as shown. The cathode of,Fig; 3 has a grid of Al wires 52 over a silicon surface 51 of mono or polycrystalline material as one piece or as many platelets-discharge to the Al ring 53 is prevented by the proximity of the earthed protective ring (30). The cathode of Fig. 4 has provision for varying the exposed area of Al. Al ring 65 with its attached Al sectors 62 may be rotationally disposed with respect to the other Al ring 64 and sectors 63 to vary the relative exposed area of Si 61 and Al. In a modification the anode may be modified so' that resistance monitoring of the deposited nitride may be used to control the thickness of the deposit. |
