Bipolar transistor, semiconductor device, and bipolar transistor manufacturing method

A semiconductor device comprising:

• a first bipolar transistor on a substrate;
• and
• a second bipolar transistor on the substrate,
• wherein the first bipolar transistor comprising:
• a first collector layer that has a long-side direction and a short-side direction in a plan view, wherein the short-side direction is parallel to crystal orientation [011], a cross-section perpendicular to the short-side direction has an inverted mesa shape, and a cross-section perpendicular to the long-side direction has a forward mesa shape;
• a first base layer that is formed directly on the first collector layer such that the first base layer contacts the first collector layer;
• a first base electrode that is formed directly on the first base layer such that the first base electrode contacts the first base layer;
• and
• a first base line that is connected to the first base electrode and that is drawn out from an end in the short-side direction of the first collector layer to the outside of the first collector layer in a plan view;
• and
• wherein the second bipolar transistor comprising:
• a second collector layer that has a long-side direction and a short-side direction in a plan view, the long-side direction of the second collector layer being parallel to crystal orientation [011];
• a second base layer that is formed on the second collector layer;
• a second base electrode that is formed on the second base layer;
• and
• a second base line that is connected to the second base electrode and that is drawn out from an end in the long-side direction of the second collector layer to the outside of the second collector layer in a plan view.