The authors have demonstrated a novel resonant interband tunneling device with GaSb/AlSb/InAs/GaSb/AlSb/InAs structures. It is found that InAs well thicknesses have a significant influence on the I-V characteristics of this device. The incorporation of an InAs layer in the well region will promote a peak-to-valley ratio of 20 at 300 K, nearly five times larger than that of the primitive one. Furthermore, multiple negative differential resistance behavior was obtained with InAs well thicknesses were in the range of 120 A to 300 A. Otherwise, single negative resistance is obtained. The significant influence of the added InAs layer on the electrical performance of the corresponding structure is found to be due to the electron-light hole coupling effect.