For p-i-n quantum confined solar cells, best efficiency trade-off is often achieved in the vicinity of a critical intrinsic region thickness corresponding to a critical builtin electric field. Nevertheless, even for devices satisfying such condition, the carrier escape sequence is shown to have a profound impact on device performance. Here, we present several correlations between photoluminescence and theoretical calculation results for studies made on specific devices. The study underlines the need to carefully consider carrier escape processes in order to achieve the goal of highly efficient quantum confined solar cell © 2006 IEEE.