We demonstrate the self-catalyst (SC) growth of vertically aligned InAs and InAs/GaSb heterostructure nanowires on Si(111) substrate by Metal Organic Chemical Vapor Deposition (MOCVD). The effect of growth temperature on morphology and growth rate for SC InAs and InAs/GaSb heterostructure nanowires (NWs) were investigated. Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) measurements revealed the morphology and shell thickness can be tuned by the growth temperature. Electron microscopy also shows the formation of GaSb both in radial and axial directions outside the SC InAs NW core at certain growth temperatures. Crystal structure of InAs/GaSb heterostructure nanowires was also discussed. These results show that the control over SC InAs NWs growth, the GaSb shell thickness and it's crystal quality was achieved which is essential for future nano electronic devices such as TFET.