Bonding structure and semiconductor device manufacturing apparatus
The present invention relates to a bonding structure, including: a ceramic member including a hole; a terminal embedded in the ceramic member, an exposed surface exposed to a bottom portion of the hole, and made of a refractory metal having a thermal expansion coefficient substantially equal to a thermal expansion coefficient of the ceramic member; a brazed bond layer including a first tantalum layer in contact with the exposed surface of the terminal, a gold layer formed on the first tantalum layer, and a second tantalum layer formed on the gold layer; and a connecting member inserted in the hole, bonded to the terminal via the brazed bond layer, and made of a refractory metal having a thermal expansion coefficient substantially equal to the thermal expansion coefficient of the ceramic member.
1. A bonding structure, comprising:
a ceramic member including a hole;
a terminal embedded in the ceramic member, including an exposed surface exposed to a bottom portion of the hole, and made of a refractory metal having a thermal expansion coefficient substantially equal to a thermal expansion coefficient of the ceramic member;
a brazed bond layer including a first tantalum layer in contact with the exposed surface of the terminal, a gold layer formed on the first tantalum layer, and a second tantalum layer formed on the gold layer; and
a connecting member inserted in the hole, bonded to the terminal via the brazed bond layer, and made of a refractory metal having a thermal expansion coefficient substantially equal to the thermal expansion coefficient of the ceramic member.
2. The bonding structure according to claim 1 , wherein
the ceramic member is made of aluminum nitride, and
the refractory metal is molybdenum.
3. The bonding structure according to claim 1 , wherein
a thickness of the gold layer is more than 0.05 mm but less than 0.3 mm, when a diameter of the brazed bond layer is not less than 4 mm but not more than 6 mm, and when a thickness of both of the first tantalum layer and the second tantalum layer are respectively 0.01 mm.
4. The bonding structure according to claim 1 , wherein
a thickness of both of first tantalum layer and the second tantalum layer is not less than 0.01 mm but less than 0.07 mm, respectively, when a diameter of the brazed bond layer is not less than 4 mm but not more than 6 mm, and when a thickness of the gold layer is 0.15 mm.
5. The bonding structure according to claim 1 , wherein
a braze pool space is formed in a part of a side surface of the hole,
the braze pool space has a substantially semicircular shape in a cross-sectional plane in parallel with a main surface of the ceramic member, and
the braze pool space is partially filled with a braze material.
6. The bonding structure according to claim 5 , wherein
the connecting member includes a protruded portion having a substantially semicircular shape in the cross-sectional plane, and the braze pool space and the protruded portion forms a locking portion.
7. The bonding structure according to claim 5 , wherein
the connecting member includes a recessed portion on a circumferential surface of the connecting member, and
the recessed portion is partially filled with a braze material.
8. The bonding structure according to claim 1 , wherein
a groove filled with a braze material formed on the exposed surface of the terminal, and the braze material filling the groove serves as an anchor.
9. The bonding structure according to claim 5 , wherein
the number of braze pool spaces formed in the surface of the hole is two to four.
10. The bonding structure according to claim 9 , wherein
one pair or two pairs of the braze pool spaces are formed at a mutually-opposed location in the surface of the hole.
11. A semiconductor device manufacturing apparatus comprising the bonding structure according to claim 1 .