METHOD FABRICATING SUB-MICRON EMITTER USING ANISOTROPIC ETCH CHARACTERISTIC

摘要

PURPOSE: A method for fabricating a sub-micron emitter using an anisotropic etch characteristic is provided to form stably a heterojunction bipolar transistor by etching easily an InGaAs layer around an emitter electrode. CONSTITUTION: A dummy emitter including an InGaAs layer(32) is laminated on a structure of a heterojunction bipolar transistor of a semiconductor substrate(31). The first line width is defined on the dummy emitter by using a photoresist. The second line width is formed on a boundary between the emitter region and the bottom of the InGaAs layer by performing an anisotropic etch process for the InGaAs layer. An emitter electrode(111) is formed by depositing a contact metal material on an anisotropic etch groove and etching the dummy emitter around the contact metal. The third line width is formed on a boundary between the base region and the bottom of the emitter region by performing the anisotropic etch process for the emitter region.