On the properties of impurity bands generated in P-type homoepitaxial diamond

Impurity band structure of boron-doped homoepitaxial diamond

“…15 In this experiment, 5000 ppm of the B 2 H 6 / CH 4 ratio corresponds to N B =2ϫ 10 19 cm 3 . 21 In order to verify the Hubbard U mechanism, we fabricated p + / p − / p + mesa structures by the method reported before, where p + is 5000 ppm boron-doped diamond having a VRH conductivity and p − is 500 ppm boron-doped diamond having a valence-band conductivity.…”

“…2 In diamond, the change from ⑀ 1 to ⑀ 2 is not observed, 8,9,14 though it is obvious that there is a temperature region which shows two-band conduction. 7,9,15 Homoepitaxial diamond growth technique provides us with samples with a smooth and clean interface so that we can fabricate thin diamond layers with an accurate impurity concentration with few trapping states at the interface. 16,17 Using this technique we fabricated p + / p − / p + mesa structure with thin p − layer, where p + is heavily doped diamond with VRH and p − is less-doped diamond with valence band conductivity.…”

Evolution of the Impurity Band to Diamond-Like Valence Bands in Boron Doped Diamond

“…There was a clear change of conductivity from the valence band to the variable range hopping (VRH) when N B ' 4 Â 10 18 cm ¹3 . 16) From the conductivity and Hall measurements, the B/C = 10,000 ppm sample had N B ¼ 2 Â 10 19 cm 3 , 12) which was one order of magnitude smaller than N c .…”

“…The ratio of B/C in the reaction gas phase was used to identify the samples, which was twice the value of that used in the previous papers, where the ratio of B 2 H 6 /CH 4 was used. [15][16][17] The boron concentration determined by a secondary ion mass spectroscopy was 1 to 10 Â 10 19 cm ¹3 in the 10,000 ppm B/C sample. 18) The boron-doped layer thickness was 1.6 µm.…”