Liquid No.1 is a mixture of hydrogen peroxide

ammonia and water.In order to provide data supports for new process development and on-line process maintenance

corrosion characteristics of titanium adhesion layer of wafer-level packaging for MEMS in liquid No.1 is studied.The results show that corrosion rate of titanium is proportional to the content of hydrogen peroxide

due to the concentration of OOH

-

ion

the effective group for titanium corrosion

increases with the increasing content of hydrogen peroxide.Corrosion rate of titanium decreases with the increasing content of ammonia

because ammonia can promote the decomposition and ionization of hydrogen peroxide

reduces concentration content of hydrogen peroxide

promotes metastable and highly soluble Ti（OH）

2

O

2

to transform into insoluble Ti（OH）

4

or oxide precipitation

which hinders the reaction through adhering to the surface of titanium.The corrosion rate of titanium decreases with the placing time of liquid No.1

due to the continuous ionization and gradual attenuation of hydrogen peroxide.Because of the existence of natural oxide layer

the corrosion rate of titanium is slowly at the beginning and then increases obviously after the natural oxide layer is washed away.