A regrowth is performed on the exposed surfaces using an amphi conductivity impurity as a dopant, such that {HEAD ~ a first portion} having {TAIL ~ a first type conductivity} is grown on the contact groove and a second portion having a second type conductivity is grown on the ridge 
having
A regrowth is performed on the exposed surfaces using an amphi conductivity impurity as a dopant , such that { HEAD ~ a first portion } having { TAIL ~ a first type conductivity } is grown on the contact groove and a second portion having a second type conductivity is grown on the ridge
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH