If I recall correctly, Victor Frankenstein finds that it isn't possible to reanimate dead tissue, and the suggestion is that his creation is animated inorganic matter akin to the golem in Jewish folklore. The subtitle of the novel is "The Modern Prometheus". In Latin mythology (unlike the Greek version), Prometheus makes man from clay and water (like a golem) and is punished by his creation, not Zeus.
In the novel, Frankenstein is interested in Galvanism (electricity) and not steam power, so not really steampunk even if the term were applied retrospectively. I don't think that there is any description that he uses electricity to animate the creature.