InGaN-based green light-emitting diodes (LEDs) with different green quantum well numbers grown on Si (111) substrates by metal organic chemical vapor deposition are investigated.It is observed that V-shaped pits appear in the AFM images with the green quantum well number increasing from 5 to 9,and results in larger reverse-bias leakage current.Meanwhile,in the case of the sample with the number from 5 to 7 then to 9,the exteal quantum efficiency increases firstly,and then decreases.These phenomena may be related to the size of V-shaped pits in the active area and the distribution of electrons and holes in the active area caused by V-shaped pits.The optimal number of green quantum wells is determined to be 7.