Techniques for low temperature ion implantation are provided to improve the throughput. During a low temperature ion implantation, an implant process may be started before the substrate temperature is decreased to be about to a prescribed implant temperature by a cooling process, and a heating process may be started to increase the substrate temperature before the implant process is finished. Moreover, one or more temperature adjust process may be performed during one or more portion of the implant process, such that the substrate temperature may be controllably higher than the prescribe implant temperature during the implant process.