The micro-cavity characteristics of vertical-cavity surface-emitting lasers (VCSELs) and the time inversion characteristics of phase conjugate feedback (PCF) are considered, the compound cavity model with PCF is set up based on the typical dynamical equation of semiconductor lasers. When the feedback index is below 0.05, the dynamics of VCSELs and side emitters are different due to their cavity size. The number of chaotic bands and their range for the two types are discussed in this paper. The phase change cumulated for PCF is zero, so the nonlinearity for VCSELs under this feedback mechanism is more complex. Three chaotic bands can be seen for common optical feedback (COF) mechanism; while only two chaotic bands can be seen for PCF and the steady state regions are larger than those of COF. A phenomenal is found that in the creation process of the chaos attractor, the phase diagram for optical field with COF is symmetric, but it is a symmetry-founding process in the case of PCF.