MOVPE deposition of AlAs/In/sub 0.53/Ga/sub 0.47/As/InP resonant tunnelling heterostructure performing high PVR parameter

The RT (Resonant Tunnelling) AIAs/Ino 53Ga 4.1As/l# heterostructure employed in our measurements was deposited on nominally (001) oriented I# S n+ (2x10 'cm )substrates The layer sequence was as follows (i) 600nm n+ InP.Si bottom contact layer (n=S~lO'*cm-~()i,i ) 600 nm nf Inos3Gao47As contact layer (n=5~10'*cm'~)(,i ii) 100 nm n In0 53Ga047As Si contact layer (n=l~lO'~cm''), (iv) 5nm undoped IQ s~Ga47As spacer layer, (v) 4 3nm undoped AlAs barrier layer, (vi) 5nm undoped In0 53Gao 47As quantum well layer, (vii) 4 3nm undoped AlAs barrier layer, (viii) 5nm undoped InossGao47As spacer layer, (ix) 100 nm n InoaGao47As.Si contact layer (n=l~lO"cm~~(x)), 100 nm n+ I ~ I o ~ ~ G Qco~nt~acAt s layer (n=5x10'*cniJ) Undo ed LP MOVPE layers have typically not intentional n-type doping level of about 2 ~ 1 0 ' ~ c mTh~e ~sc heme of the epilayers design concerning our RTS (Resonant Tunnelling Structure).