Early research on Space-Time-Frequency (STF) codes are aimed at achieving maximum frequency and spatial diversity only. Over a space-time-frequency selective fading channel, there is a possibility of achieving better performance if coding across spatial, temporal, and spectra dimensions is designed properly. To date, only two STF codes were proposed to achieve full diversity. The decoding complexity, however, of these codes is prohibitive. In this paper, full diversity STF codes with linear decoding complexity are proposed. Simulation results over 3GPP-SCM are presented to support the code designs.