GaAs器件镀层应力问题分析及解决

Analysis and Solution of Coating Stress on GaAs Device

传统的GaAs电镀布线工艺,镀层金属与种子层呈锐角,导致氮化硅表面出现变色脱落等现象,影响器件稳定性和可靠性。本文改进了传统的电镀布线工艺,在电镀布线后,表面先涂覆薄层聚合物(0.5μm以内)以消除锐角,消除应力集中点,之后再淀积氮化硅,形成复合保护层。改进后的工艺解决了因镀层金属应力集中导致的氮化硅表面变色和脱落等问题。

In the traditional GaAs electroplating wiring process,the coating metal and seed layer have an acute angle,which leads to the phenomenon of discoloration and falling off on the surface of silicon nitride,which affects the stability and reliability of the device.In this paper,the traditional electroplating wiring process is improved.After the electroplating wiring,a thin layer of polymer is coated on the surface to eliminate the acute angle and stress concentration point,and then silicon nitride is deposited to form a composite protective layer.The improved process solves the problems of discoloration and peeling of silicon nitride surface caused by stress concentration of coating metal.