self-generated vs spontaneous

self-generated and spontaneous both are adjectives.

Word	Noun	Adjective	Verb	Adverb
self-generated	No	Yes	No	No
spontaneous	No	Yes	No	No

As adjectives, self-generated and spontaneous are synonyms defined as:

self-generated and spontaneous: happening or arising without apparent external cause

self-generated (adjective)	spontaneous (adjective)
happening or arising without apparent external cause	happening or arising without apparent external cause
originating from the self	said or done without having been planned or written in advance