METHOD FOR MANUFACTURING BIPOLAR JUNCTION TRANSISTOR

摘要

PURPOSE: A method for manufacturing a bipolar junction transistor is provided to simplify the manufacturing process and reduce the step between a base poly layer and an emitter poly layer by using an oxide spacer. CONSTITUTION: An isolation layer(32) is formed on a silicon substrate(30). A base poly layer(34) is deposited on the silicon substrate. An ion implantation is carried out on the base poly layer. The first oxide layer is deposited on the base poly layer. An emitter window is formed by trenching the base poly layer and the silicon substrate. An oxide spacer(40) is formed at both sidewalls of the emitter window. An emitter poly layer(42) is deposited on the resultant structure. An ion implantation is carried out on the emitter poly layer. The second oxide layer is deposited on the resultant structure. An emitter junction region is formed by carrying out an annealing process. The second oxide layer is removed. The emitter poly layer is partially removed by carrying out a CMP(Chemical Mechanical Polishing) process.