joh-eun -ahchim good morning right
Yes. 좋은 아침 (joh-eun ahchim) is “good morning” (좋은=good, 아침=morning).
This is actually a greeting borrowed directly from English. Before the 1980s this phrase just did not exist (I challenge anyone to find a usage of it in any text or media created before 1980).
Some people felt an acute need for “good morning”, particularly in workplaces and among the younger generation, and started using it sometime in the 80s. Although it gradually gained popularity since, I believe it is still nothing like other common greetings in terms of usage.
So it is not just an equivalent phrase to “good morning” but more like a translation of it.