open a link in a new tab

hi dears,
for opening a link in a new tab, i am using the code like as follows
 Response.Write("<script language='javascript'>window.open('http://www.ddd.com/Legendle.htm','');</script>")
this code is working fne in firefox,but when i tested with explorer 8 window is showing in a new window instead of a new tab?how can i solve this issue?
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