For what its worth, as a former tech recruiter, a female candidate had a 90% chance of hire at 70% or greater hire rate then a male candidate.
What that means is, if the company felt the female candidate was less qualified, but had potential then another male candidate, they would be hired. And, all things being equal (subjectively), had a greater opportunity of hire rate (our fee's, thus tracked). "Get a female in tech, get a placement," theoretically spoken.
I am just agreeing with MChurch mostly. It may however, not be so granular as he cites, rather, the fact that the % of females in the area of tech is so low, that selection bias towards females becomes an "issue" to look for more female candidates.
In other words (because I tend to ramble and befuddle what I am trying to say), little females exist in tech. If you get a qualified candidate in tech that is female, that is a more rare event, and thus worth more attention and notice (subconscious or otherwise).