| 摘要 |
<p>1,189,355. Semi-conductor devices. PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd. 12 May, 1967 [17 May, 1966], No. 22096/67. Heading H1K. One electrode 7 of a junction-gate field effect transistor is shielded from the main bulk 2 of the semi-conductor body which comprises the gate region, by means of a shielding layer 13 which is electrically connected to the other electrode 6 of the transistor. In the embodiment shown the shielding layer 13 comprises an N-type surface region of the semi-conductor body connected to the N-type source (or drain) region 4 by a region 15. The shielding layer is isolated from the P-type bulk 2 of the body by the junction 14. The shielding layer may alternatively comprise a metal coating insulated from the body 2 by an insulating coating, e.g. of silicon oxide or silicon nitride, and connected to the electrode 6 by a conductor deposited on the insulating coating. In the form illustrated the electrodes 6, 7 are interdigitated and are connected to the source and drain regions through apertures in the insulation 3. The body 2 is of P-type silicon 61 carrying a relatively high resistivity N-type epitaxial layer 62. Diffusion of boron through a mask isolates the required N-type pattern, and a further diffusion of phosphorus between the source and drain regions converts some of the material there to P-type and thus restricts the thickness of the N-type channel. The electrodes 6, 7 are of vapour deposited aluminium selectively etched to the required shape. Alternatively the device may be manufactured simply by two diffusion steps into a substrate. The semi-conductor body may also be of germanium or an A III B V compound. Two independently connected gate regions may be provided, and the shielding layer may be connected to the electrode 6 outside the envelope which encloses the device.</p> |
