The effects of strain and In content upon dislocation reduction was studied by introducing an InGaAs strained layer into a GaAs layer on a Si substrate. The 2 influences were separated by using the strain energy that accumulated in the InGaAs layer, since the strain in such a layer varied with the In content. The results showed that the variation in dislocation density depended upon the strain and not upon the In content. A strain energy of 250dyn/cm was sufficient to reduce the dislocation density effectively in both the InGaAs layer and the GaAs over-layer. When the strain energy was greater than 500dyn/cm, the number of dislocations increased when an InGaAs layer was introduced.

Y.Uchida, Y.Yazawa, T.Warabisako: Applied Physics Letters, 1995, 67[1], 127-9