The striker ended his spell at Letzigrund on Tuesday, joining the La Liga side in a four-year deal.
Although he reached high heights in helping The City Club win the Swiss Cup, there were equally low moments for the 23-year-old whose career suffered a major setback last summer when a move to English outfit Huddersfield Town fell through at the last hour due to a failed medical.
He took to social media to thank the Swiss side for their unconditional support.
In January 2017, Dwamena joined Zurich from Austria Lustenau after raking in 18 league goals for the Austrian club.
In his first season in Switzerland, he notched 12 goals in 18 matches to help FCZ secure topflight promotion.
He continued his good form in the elite division as he registered nine goals in 32 games.
Dwamena, who scored twice on his international debut for Ghana last year, was once on the books of Austrian giants Red Bull Salzburg, featuring for feeder side Liefering.