PHYSICAL QUANTITY MEASUREMENT DEVICE AND METHOD FOR MANUFACTURING SAME, AND PHYSICAL QUANTITY MEASUREMENT ELEMENT
It is an object to provide a highly reliable physical-quantity measurement device which can relax thermal stress at a time of bonding and suppress creep or drift of a sensor output. To attain the above-described object, a physical-quantity measurement device according to the present invention includes a semiconductor element, and a base board connected to the semiconductor element with a plurality of layers being interposed. In the plurality of layers, a stress relaxing layer including at least metal as a main ingredient and a glass layer including glass as a main ingredient are formed each in a layered form including one or more layers. At least one of the stress relaxing layer and the glass layer includes low-melting-point glass, and a softening point of the low-melting-point glass is equal to or lower than the highest heat temperature that the semiconductor element can resist.
1 . A physical-quantity measurement device comprising:
a semiconductor element; and
a base board connected to the semiconductor element with a plurality of layers being interposed, wherein
the plurality of layers include:
a stress relaxing layer including metal as a main ingredient;
an insulating layer; and
a bonding layer including low-melting-point glass that has a softening point equal to or lower than the highest heat temperature that the semiconductor element resists.
2 . A physical-quantity measurement device comprising:
a semiconductor element; and
a base board connected to the semiconductor element with a plurality of layers being interposed, wherein
the plurality of layers include:
a stress-relaxing bonding layer in which a content by volume of metal is 50% to 90%, the stress-relaxing bonding layer including low-melting-point glass that has a softening point equal to or lower than the highest heat temperature that the semiconductor element resist; and
an insulating layer.
3 . The physical-quantity measurement device according to claim 1 , wherein
the stress relaxing layer is placed between the semiconductor element and the insulating layer, and/or between the insulating layer and the base board.
4 . The physical-quantity measurement device according to claim 1 , wherein
the stress-relaxing bonding layer is placed between the semiconductor element and the insulating layer, and/or between the insulating layer and the base board.
5 . The physical-quantity measurement device according to claim 1 , wherein
the metal includes at least one kind selected from Ag, Cu, Al, Ti, Ni, Mo, Mn, W, and Cr.
6 . The physical-quantity measurement device according to claim 1 , wherein
the low-melting-point glass includes at least two kinds or more out of a vanadium element, a silver element, and a tellurium element.
7 . The physical-quantity measurement device according to claim 1 , wherein
the stress relaxing layer is a sputtered layer or a plating layer.
8 . The physical-quantity measurement device according to claim 1 , wherein
a thickness of the stress relaxing layer is 0.05 μm or more to 10 μm or less in total.
9 . The physical-quantity measurement device according to claim 8 , wherein
the thickness of the stress relaxing layer is 1.5 μm or more to 5 μm or less in total.
10 . The physical-quantity measurement device according to claim 2 , wherein
a thickness of the stress-relaxing bonding layer is 0.05 μm or more to 10 μm or less in total.
11 . The physical-quantity measurement device according to claim 10 , wherein
the thickness of the stress-relaxing bonding layer is 1.5 μm or more to 5 μm or less in total.
12 . The physical-quantity measurement device according to claim 2 , wherein
the content by volume of the metal in the stress-relaxing bonding layer is 50% to 70%.
13 . A method for manufacturing a physical-quantity measurement device, comprising the steps of:
forming a bonding-layer forming paste by mixing a metallic filler with low-melting-point glass in such a manner that a content by volume of the metallic filler is equal to or larger than 50%;
forming a bonding material by coating one of surfaces of a glass substrate with the bonding-layer forming paste and carrying out heat treatment;
placing the bonding material between a semiconductor element and a base board; and
bonding the semiconductor element and the base board by heating the semiconductor element and the base board at a heating temperature that is equal to or higher than a softening point and is equal to or lower than the highest heat temperature that the semiconductor element resist.
14 . The method for manufacturing a physical-quantity measurement device according to claim 13 , wherein
the heating temperature is equal to or lower than 300° C.