Hi Changjie Bai,
The only thing you can do is have Apple perform an "out-of-warranty" replacement. Prices for an iPad 3 start at $299 and go up from there depending on model. Seehttp://support.apple.com/kb/index?page=servicefaq&geo=United_States&product=ipad
Certain damage is ineligible for out-of-warranty service, including catastrophic damage, such as the device separating into multiple pieces, and inoperability caused by unauthorized modifications. However, an iPad that has failed due to contact with liquid may be eligible for out-of-warranty service. For the most part, shattered screens will be covered too (as long as the iPad body is still in tact). We've done OOW replacements in our school distrcit for cracked screens before.
There are some third party vendors who can replace the screen for less, but doing so will void any future warranty you have with Apple.
I know this isn't the answer you wanted to hear, but I hope it answers your question.