The genre heavily relies on elements of science fiction or fantasy. The major motive are the sinister consequences of modern science/technology, used either by evil actors towards their evil goals, or by benevolent actors who lose control and things go horribly wrong. This subgenre notably belongs to Western civilization and Japan and does not exist in China, India, Egypt, etc.
First techno-horror films were produced in big numbers in 1950s, most of them being of low quality and undeserving of critical review, with some exceptions, such as The Day the Earth Stood Still (1951) or Forbidden Planet (1956). 
A yet another form of techno-horror is inclusion of technology into otherwise classical narratives. An example is the evolution J-horror genre: classical "scares", such as ghosts, spirits, curses, etc., propagate via hi-tech media: computer networks, cell phones, etc. Here, modern technology is not a threat per se, but rather a new conduit for various dark forces.
- Tony Magistrale, Abject Terrors: Surveying the Modern and Postmodern Horror Film, 2005 p. 82
- Sonny Bunch, "Techno-Horror in Hollywood. Japanese Anxieties, American Style", The New Atlantis, Number 14, Fall 2006, pp. 137-140.