Method and system for diamond-based oxygen sensor
A diamond based oxygen sensor is able to function in harsh environment conditions. The oxygen sensor includes a gateless field effect transistor including a synthetic, quasi-intrinsic, hydrogen-passivated, monocrystalline diamond layer exhibiting a 2-dimension hole gas effect. The oxygen sensor also includes a sensing layer comprising yttrium-stabilized zirconia deposited onto a surface of the gateless field effect transistor.
1. An oxygen sensor, comprising:
a gateless field effect transistor (FET) ( 100 ) including a synthetic, quasi-intrinsic, hydrogen-passivated diamond layer ( 116 ) exhibiting a 2-dimension hole gas effect; and
an oxygen-sensing layer ( 124 ) including a yttrium-stabilized zirconia (YSZ) supported by the gateless FET ( 100 ).
2. The oxygen sensor of claim 1 , the gateless FET ( 100 ) further including:
a first highly-doped p-type region ( 118 ) implanted within the monocrystalline diamond layer ( 116 );
a second highly-doped p-type region ( 120 ) implanted within the monocrystalline diamond layer ( 116 ); and
a 2-dimension hole gas conductive channel ( 128 ) within the monocrystalline diamond layer ( 116 ) between the first highly-doped p-type region ( 118 ) and the second highly-doped p-type region ( 120 ).
3. The oxygen sensor of claim 2 , the gateless FET ( 100 ) further including:
an ohmic source contact ( 122 ) electrically coupled to the first highly-doped p-type region ( 118 ); and
an ohmic drain contact ( 126 ) electrically coupled to the second highly-doped p-type region ( 120 );
wherein the oxygen-sensing layer ( 124 ) is supported by the 2-dimension hole gas conductive channel ( 128 ) and electrically coupled between the ohmic source contact ( 122 ) and the ohmic drain contact ( 126 ).
4. The oxygen sensor of claim 2 , the gateless FET ( 100 ) further including a polycrystalline diamond substrate ( 114 ), wherein the monocrystalline diamond layer ( 116 ) is grown on a first side of the polycrystalline diamond substrate ( 114 ).
5. The oxygen sensor of claim 2 , the gateless FET ( 100 ) further including an ohmic contact substrate ( 112 ) supported by a second side of the polycrystalline diamond substrate ( 114 ).
6. The oxygen sensor of claim 2 , wherein:
the first highly-doped p-type region ( 118 ) is implanted within the monocrystalline diamond layer ( 116 ) using boron implantation; and
the second highly-doped p-type region ( 120 ) is implanted within the monocrystalline diamond layer ( 116 ) using boron implantation.
7. The oxygen sensor of claim 2 , wherein:
the 2-dimension hole gas conductive channel ( 128 ) is formed within the monocrystalline diamond layer ( 116 ) by performing hydrogen passivation.
8. The oxygen sensor of claim 3 , wherein the ohmic source contact ( 122 ) and the ohmic drain contact ( 126 ) are formed using a stack of Ti/Au.
9. A method of forming a gateless FET oxygen sensor, comprising:
forming a gateless field effect transistor (FET) ( 100 ); and
forming an oxygen-sensing layer ( 124 ) including a yttrium-stabilized zirconia (YSZ) supported by the gateless FET ( 100 ).
10. The oxygen sensor of claim 9 , wherein forming the gateless FET ( 100 ) includes:
growing a synthetic, quasi-intrinsic, hydrogen-passivated diamond layer ( 116 ) on a first side of a polycrystalline diamond substrate ( 114 );
generating a first highly-doped p-type region ( 118 ) within the monocrystalline diamond layer ( 116 );
generating a second highly-doped p-type region ( 120 ) within the monocrystalline diamond layer ( 116 ); and
generating a 2-dimension hole gas conductive channel ( 128 ) within the monocrystalline diamond layer ( 116 ) between the first highly-doped p-type region ( 118 ) and the second highly-doped p-type region ( 120 ).
11. The oxygen sensor of claim 10 , wherein forming the gateless FET ( 100 ) further includes:
disposing an ohmic source contact ( 122 ) on the first highly-doped p-type region ( 118 ); and
disposing an ohmic drain contact ( 126 ) on the second highly-doped p-type region ( 120 ).
12. The oxygen sensor of claim 10 , wherein forming the gateless FET ( 100 ) further includes disposing an ohmic contact substrate ( 112 ) on a second side of the polycrystalline diamond substrate ( 114 ).
13. The oxygen sensor of claim 10 , wherein the first highly-doped p-type region ( 118 ) and the second highly-doped p-type region ( 120 ) are generated within the monocrystalline diamond layer ( 116 ) using boron implantation.
14. The oxygen sensor of claim 10 , wherein the 2-dimension hole gas conductive channel ( 128 ) is generated within the monocrystalline diamond layer ( 116 ) by performing hydrogen passivation.
15. The oxygen sensor of claim 11 , wherein the ohmic source contact ( 122 ) and the ohmic drain contact ( 126 ) are formed using a stack of Ti/Au.