BIPOLAR TRANSISTOR AND METHOD OF MANUFACTURING THE SAME

PROBLEM TO BE SOLVED: To improve high speed characteristics and reliability of HBT. SOLUTION: A first insulating film 108 comprising silicon nitride (SiN) is formed on a side of part of an emitter mesa and a surface of a ledge structure 105a so that those parts are covered. Also, a second insulating layer 109 comprising the silicon nitride is formed extended (crossing) from a periphery of the first insulating layer 108 to an upper surface of a base electrode 111. A second insulating layer 109 is formed so that a side of the first insulating film 108, an upper part of a base layer 104 between the ledge structure 105a and base electrode 111 and un upper surface of the base electrode 111 are covered. An external shape of the ledge structure 105a is formed so as to be the same as that of the first insulating layer 108 in a planar direction of a substrate 101. Also, a periphery of the base electrode 111 in a direction distant from the emitter mesa is formed so as to overlap with the periphery of the first insulating layer 108. COPYRIGHT: (C)2011,JPO&INPIT