| 摘要 |
1306817 Semi-conductors INTERNATIONAL BUSINESS MACHINES CORP 3 Nov 1970 [10 Nov 1969] 52156/70 Heading H1K A monolithic semi-conductor device comprises a P-type S1<SP>1</SP> substrate 1 with a surface layer 2 of Si O 2 into which a window 3 is etched over photoresist through which P and A s are diffused into the substrate to produce overlying impurity regions (Fig. 1C). Oxide 2 is removed and a P-epitaxial layer 5 is grown, after which an oxide layer 10 is formed thereon and the As and P dopants are out-diffused until P reaches the upper surface of layer 5 (Fig. 1E) to form a pocket of N-type material extending within layer 5 and substrate 1, having regions 12 of heavily doped N+ material containing As and P lightly doped region 3 of N material containing out-diffused P. A transistor is formed by opening a window in layer 10 and diffusing P-type base region 16 with B dopant within region 13 (Fig. 1G) and emitter and collector N+ regions 19, 20 through other windows 17, 18 with P or As dopant (Fig. 1H). The dopants may be introduced simultaneously from a mixed source, or successively from separate sources, e.g. thermally; followed by heat treatment in most oxygen for out-diffusion and oxidation. The substrate may itself be epitaxially deposited. Collector-substrate insulation is-formed by the N-P junction between regions 13 and 1, 5 while buried layer 12 reduces collector resistance of a bipolar transistor within region 11, within which diffused resistors may be formed. The NP isolation junction has reduced isolation capacitance. Impurity distribution profiles (Figs. 2, 3 not shown) and typical structural and operating parameters-are given.
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