Heterojunction bipolar transistor structure and manufacturing method thereof

Abstract

The invention discloses a heterojunction bipolar transistor structure and a manufacturing method thereof. The method comprises the following steps: carrying out etching on a semiconductor device withemitter contact metal to etch off a cap layer around the emitter contact position and retain the cap layer under the emitter contact position and around the semiconductor device; depositing a first protection layer; etching the base contact position to etch off the first protection layer and an emitter layer on the base contact position; depositing base contact metal at the base contact position;depositing a second protection layer; etching the base table position to etch off the second protection layer, the first protection layer, the emitter layer, the base layer and a part of collector layer around the base table position and retain the structure around the semiconductor device. The scheme can avoid generation of arrow shadow, improve product yield rate and reduce parasitic capacitance, thereby reducing radio frequency loss.

Description

technical field [0001] The invention relates to the field of transistor manufacturing, in particular to a structure and a manufacturing method of a heterojunction bipolar transistor. Background technique [0002] The structure of the commonly used HBT (heterojunction bipolar transistor) is as follows: figure 1 shown. The plateau (such as figure 1 (shown by the dotted line) is very high relative to the two sides, and there is a great risk of arrow shadows when coating photoresist. Moreover, when making the first metal layer M1 and the second metal layer M2, polyimide PI needs to be used for flatness. PI is used as the dielectric layer between the metal connection of the first layer and the metal connection of the second layer, which will cause parasitic capacitance between the metal of the first layer of connection and the metal of the second layer of connection. It will affect the device characteristics and eventually cause radio frequency loss. Contents of the inventi...

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Problems solved by technology

[0003] To this end, it is necessary to provide a heterojunction bipolar transistor structure and manufacturing method to solve the problems that the existing heterojunction bipolar transistor manufacturing process may have photoresist arrow shadows and the use of polyimide may produce parasitic capacitance.

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