Regex bug?

Hello

This regex: name="(.*)_<\?=\$i;\?>_(.*)"

mark all this sentence:

name="section_<?=$i;?>_Cta_url" type="text" width=""

while 

this one: name="(\w)_<\?=\$i;\?>_(\w)"

marks nothing

what should I put as regex to find only this part:

name="section_<?=$i;?>_Cta_url"

?