| CPC H01L 33/06 (2013.01) [H01L 21/02381 (2013.01); H01L 21/02389 (2013.01); H01L 21/0242 (2013.01); H01L 21/02458 (2013.01); H01L 21/02472 (2013.01); H01L 21/02483 (2013.01); H01L 21/02507 (2013.01); H01L 21/0251 (2013.01); H01L 21/0254 (2013.01); H01L 21/02554 (2013.01); H01L 21/02565 (2013.01); H01L 27/15 (2013.01); H01L 33/007 (2013.01); H01L 33/10 (2013.01); H01L 33/14 (2013.01); H01L 33/16 (2013.01); H01L 33/18 (2013.01); H01L 33/32 (2013.01)] | 18 Claims |

|
1. A semiconductor structure comprising:
a growth axis;
a first layer consisting of a single layer, wherein the single layer comprises:
a first semiconductor comprising a polar crystal structure with a spontaneous polarization axis that is parallel to the growth axis; and
a monotonic change in composition from a wider band gap (WBG) material to a narrower band gap (NBG) material or from a NBG material to a WBG material along the growth axis, wherein the monotonic change in composition comprises a continuous change in composition along the growth axis;
wherein the monotonic change in composition induces p-type or n-type conductivity in the first layer; and
a second layer comprising a second semiconductor with the polar crystal structure, wherein there is no abrupt change in polarization at an interface between the first layer and the second layer;
wherein the monotonic change in composition is the only monotonic change in composition in the semiconductor structure, and
wherein the first semiconductor is selected from:
aluminium gallium nitride (AlxGa1-xN) where 0≤x≤1;
boron aluminium nitride BxAl1-xN where 0≤x≤1;
aluminium gallium indium nitride (AlxGayIn1-x-yN) where 0≤x≤1, 0≤y≤1 and 0≤(x+y)≤1; and
magnesium zinc oxide (MgxZn1-xO) where 0≤x≤1.
|