Glass-moulded type semiconductor device
AssigneeHitachi, Ltd.
InventorsKensuke Suzuki, Takeshi Sasaki, Mitsuyuki Matsuzaki
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Abstract
A semiconductor device according to the present invention comprises a silicon pellet adhesively fixed with a soft solder between a pair of leads provided with headers and having a thermal expansion coefficient greatly different from those of the silicon pellet and mould glass. An assembly including the silicon pellet is then glass-moulded to provide semiconductor device. The leads are provided with a film having low wetness to glass for preventing a breakage of the mould glass due to the difference between the thermal expansion coefficients.
Claims28
A glass-moulded type semiconductor device comprising at least one semiconductor pellet having at least one p-n junction extending to a lateral circumferential surface, lead electrodes each having a thermal expansion coefficient much greater than that of said at least one semiconductor pellet and including a header portion to which said at least one semiconductor pellet can be adhesively fixed, a soft solder having a low melting point for adhesively fixing said lead electrodes to both sides of said at least one semiconductor pellet, and a mould glass having a passivation function to said at least one p-n junction of said at least one semiconductor pellet and adhesively fixed to said at least one semiconductor pellet all over the surface of its lateral circumference and having a thermal expansion coefficient substantially approximate to that of said at least one semiconductor pellet.
A glass-moulded semiconductor device comprising:
- a semiconductor pellet structure including at least one pn junction which extends to a lateral circumferential surface bounded by first and second end surfaces;
- a first lead electrode having a thermal expansion coefficient much greater than that of said semiconductor pellet structure, said first lead electrode having a header portion at one end thereof which faces said first end surface of said semiconductor pellet structure;
- a second lead electrode having a thermal expansion coefficient much greater than that of said semiconductor pellet structure, said second lead electrode having a header portion at one end thereof which faces said second end surface of said semiconductor pellet structure;
- first means, disposed between and contiguous with said first end surface of said semiconductor pellet structure and the header portion of said first lead electrode, for fixedly securing said first lead electrode to said semiconductor pellet structure and including soft solder material having a low melting point which is contiguous with both said first end surface of said semiconductor pellet structure and the header portion of said first lead electrode;
- second means, disposed between and contiguous with said second end surface of said semiconductor pellet structure and the header portion of said second lead electrode, for fixedly securing said second lead electrode to said semiconductor pellet structure and including said soft solder material having said low melting point which is contiguous with both said second end surface of said semiconductor pellet structure and the header portion of said second lead electrode;
- and
- moulded glass material for passivating said at least one pn junction and being contiguous with the entire lateral circumferential surface of said semiconductor pellet structure and having a thermal expansion coefficient approximating that of said semiconductor pellet structure;
- and wherein
- said low melting point of said soft solder material is lower than the melting point of said moulded glass material.
Dependencies are inferred from the claim text.