Wiring substrate
A wiring substrate includes a substrate with a first principal face and a second principal face. The first principal face has a first corner and first and second sides. The second principal face has a second corner corresponding to the first corner, and a third and a fourth side, respectively corresponding to the first and second sides. The substrate further comprising a first side surface connected to the first side, a second side surface connected to the second side, a third side surface connected to the third side, a fourth side surface connected to the fourth side, a first fracture part located between the first and third side surfaces to connect them, and a second fracture part located between the second and the fourth side surfaces to connect them. In the substrate's thickness direction, the length of the second side surface is smaller than the first side surface.
1. A wiring substrate, comprising:
a substrate comprising a first principal face and a second principal face opposite to the first principal face and having a rectangular shape in a plan view thereof; and
a wiring conductor,
the first principal face comprising a first corner, a first side, and a second side, the first corner being located between the first side and the second side in a plan view of the first principal face,
the second principal face comprising a second corner which is located at a position corresponding to the first corner, a third side which is located at a position corresponding to the first side, and a fourth side which is located at a position corresponding to the second side, in a plan view of the second principal face,
the substrate comprising a first side surface which is connected to the first side, a second side surface which is connected to the second side, a third side surface which is connected to the third side, a fourth side surface which is connected to the fourth side, a first fracture part which is located between the first side surface and the third side surface to connect the first side surface and the third side surface, and a second fracture part which is located between the second side surface and the fourth side surface to connect the second side surface and the fourth side surface,
in a thickness direction of the substrate, a length of the second side surface being smaller than a length of the first side surface,
the second side surface comprising a first curved part on a side close to the first corner, the first curved part being convexly curved toward the second corner and the second principal face.
2. The wiring substrate according to claim 1 , further comprising:
a first curved surface which is located between the first side surface and the second side surface in a region close to the first principal face,
wherein the first curved surface has a width gradually decreasing as going toward a center part of the substrate in the thickness direction thereof.
3. The wiring substrate according to claim 2 , wherein
in a thickness direction of the substrate, a length of the fourth side surface is smaller than a length of the third side surface, and
the fourth side surface comprises a second curved part on a side close to the second corner, and the second curved part is convexly curved toward the first corner and the first principal face.
4. The wiring substrate according to claim 3 , further comprising:
a second curved surface which is located between the third side surface and the fourth side surface in a region close to the second principal face,
wherein the second curved surface has a width gradually decreasing as going toward a center part of the substrate in the thickness direction thereof.
5. The wiring substrate according to claim 1 , wherein
in a thickness direction of the substrate, a length of the fourth side surface is smaller than a length of the third side surface, and
the fourth side surface comprises a second curved part on a side close to the second corner, and the second curved part is convexly curved toward the first corner and the first principal face.
6. The wiring substrate according to claim 5 , further comprising:
a second curved surface which is located between the third side surface and the fourth side surface in a region close to the second principal face,
wherein the second curved surface has a width gradually decreasing as going toward a center part of the substrate in the thickness direction thereof.