Research on Automatic Speech Recognition (ASR) dates back to the 1950s.
See Lecture 1 in the Columbia Speech Recognition course for an introduction.
Preethi Jyothi, IIT Bombay gives a recent overview talk at Microsoft (2017).
There is an edX online course on Speech Recognition. This is an introductory course to principles of speech recognition, created by Jasha Droppo, Mike Seltzer and Andreas Stolcke as part of Microsoft's "AI School", but really self-contained and not specific to Microsoft AI services. It's aimed at undergraduatess wishing to learn the basic principles of speech recognition.
Michael Picheny of IBM presents a review of progress in ASR in Speech Recognition: What's Left? (2018, I think). Here's Michael's abstract:
Hermann Ney (Aachen) provides an excellent tretment of the development of ASR and related Speech Tech over 40 years. This is the ISCA Medalist keynote talk at Interspeech 2021