You should provide a sample.
Maybe this is the typeface you're referring to:
http://www.ms-studio.com/FontSales/changeling.html

I was going to answer John Carpenter, but then remembered that he didn't direct the movie. But if he had, he would have designed the font.

I go into this a little bit in the PDF for Changeling Neo:

http://www.marksimonson.com/fontspecimens/ChangelingNeoSpecimen.pdf

Basically, the Terminator logo appears to have been based on a VGC font called China (the same font that my Changeling was based on). I've been able to find out nothing about the designer of China except for the name "M. Mitchell". The Terminator logo has a different "A" and "R" from China. I included a similar "A" in Changeling and Changeling Neo. I have no idea who designed the Terminator logo.