CAJ | 학술논문

研究了电化学沉积金凸点的晶圆级直径和厚度分布及表面粗糙度随电镀电流密度和镀槽温度的变化.电化学沉积的金凸点在整个晶圆上的各个位置和方向上直径都增大了.当在40℃下电镀时,金凸点的直径分布与光刻胶的分布规律相似;而电镀温度为60℃时,金凸点的直径分布更倾向于对称分布.其次,当镀槽温度从40℃提高到60℃或者电镀电流密度从8 mA/cm2降低到3mA/cm2时,金凸点的厚度分布更加均匀.再次,60℃下电镀的金凸点表面粗糙度为130到160纳米并与电镀电流密度无关,但是在40℃下电镀时,表面粗糙度随着电镀电流密度的增加从82 nm急剧增加到1572 nm.
연구료전화학침적금철점적정원급직경화후도분포급표면조조도수전도전류밀도화도조온도적변화.전화학침적적금철점재정개정원상적각개위치화방향상직경도증대료.당재40℃하전도시,금철점적직경분포여광각효적분포규률상사;이전도온도위60℃시,금철점적직경분포경경향우대칭분포.기차,당도조온도종40℃제고도60℃혹자전도전류밀도종8 mA/cm2강저도3mA/cm2시,금철점적후도분포경가균균.재차,60℃하전도적금철점표면조조도위130도160납미병여전도전류밀도무관,단시재40℃하전도시,표면조조도수착전도전류밀도적증가종82 nm급극증가도1572 nm.
Wafer level diameter and thickness distribution and surface roughness of electrochemical depo-sition (ECD) Au bumps were studied with variations of electroplating current densities and bath tempera-tures. The diameter of ECD Au bumps was enlarged at all positions and directions of the wafer. When e-lectroplated at 40℃, the diameter distribution of Au bumps was similar to that of photoresist. While elec-troplated at 60℃, its distribution was more symmetric. Secondly, more uniform thickness distribution ofAu bumps was obtained when the bath temperature increased from 40℃ to 60℃ or the electroplating cur-rent density decreased from 8 mA/cm2 to 3 mA/cm2. Thirdly, the Au bumps electroplated at 60℃ exhib-ited the surface roughness of 130 - 160 nm independent of electroplating current densities. The Au bumpselectroplated at 40℃ exhibited the surface roughness being dramatically increased from 82 nm to 1572 nmwith electroplating current density increasing.