Please don't post if you don't know what you're talking about. eCPM is earnings normalized to 1000 impressions. If you get more impressions the eCPM will not change. To increase eCPM either the CTR or the ePC or both must be increased, NOT the impressions.
One way (there are others) is to have (and keep adding) some decent content that people will want to view. As it gets indexed, more visitors are likely to find it.
CPM is just a math equation. "Essentially, effective CPM represents your estimated earnings for every 1000 impressions you receive" Don't focus on this to much, focus on targeted traffic instead. I've had $600 cpm before which didnt matter at all.
And when the clicks do not convert on the advertiser's site, you may start earning less per click and your eCPM will go back down.