关于EM的问题

关于EM的一个选择题，如下：Electro-migration (EM) decreases the reliability of ICs. For EM, which of the following statements is right (multiple choice)?
A)
EM is due to the collision of electrons to each other when they are moving in metal.
B)
High temperature will have bad impact for EM.
C)
Aluminum has higher conductivity than Copper, so Aluminum is more electro-migration-robust than Copper.
D)
Doping with some other metallic element (like Cu, Tu), Aluminum metal could build barrier for movement of iron, which is good for EM.
E)
EM may cause metal wire “open” and “short”.
F)
EM problem for power network is more serious than EM problem for normal signal.
哪几项是正确的啊?

肿么没有一个人回答呢?
求高人指教啊！

我感觉除了C以外都对

在A和D之间至少还有一个错误的，但我不知道是哪一个，或者是都错了！

C肯定是错的吧。铜应该电阻小，It is known that pure copper used for Cu-metallization is more electromigration-robust than aluminum
A 应该是错的。（应该是电子和原子）
BEF应该是对的。
D 可能是对的。
http://en.wikipedia.org/wiki/Electromigration

谢谢回复！
A应该是错的，不是电子之间的撞击，应该是电子猛烈撞击金属阳离子而导致金属阳离子发生宏观迁移。
至于D，就真不知道了！

A)
EM is due to the collision of electrons to each other when they are moving in metal.
[错吧， 是电子迁移吧，
B)
High temperature will have bad impact for EM.
【对，高温对em不利

C)
Aluminum has higher conductivity than Copper, so Aluminum is more electro-migration-robust than Copper.
[错，copper更好，
D)
Doping with some other metallic element (like Cu, Tu), Aluminum metal could build barrier for movement of iron, which is good for EM.
【应该是，合金更好，
E)
EM may cause metal wire “open” and “short”.
【对，主要是open，
F)
EM problem for power network is more serious than EM problem for normal signal.
【对，因为power net 的电流比较大，消耗的更多些，

非常感谢icfb兄的回复！
主要就是确认一下D是否是对的！

有的工艺用这种方法D是对的