Multilayers　of　Ge　quantum　dots　were　grown　on　Si　substrate　by　UHV/CVD.　The　Ge　composition　and　strain　relaxation　in　Ge　dots　by　a　rapid　thermal　annealing　(RTA)　treatment　at　different　conditions　were　characterized　by　DCXRD　and　Raman　spectrum,　and　the　influence　of　rapid　thermal　annealing　on　Ge　quantum　dots　crystal　quality　was　investigated.　The　results　show　that　the　Ge　composition　decreased　and　strain　relaxation　in　Ge　dots　increased　at　higher　annealing　temperature.　The　Ge　dots　were　almost　completely　strain　relaxed　by　RTA　treatment　at　1000°C　for　20　s.　©　Copyright.