File Name as Unique

Hi all,
Since I need to maintain the file name with time stamp as unique in unix, i need to write script.
Is there any way to capture the milli/micro seconds of unix system.
Please reply me.

It may help you:

date '+DATE: %m%d%y%H%M%S'
DATE: 021109024340

For getting nanoseconds:
date '+%N'

refer man page of date command for more details.