Resistivity of chemical vapor deposited diamond films

Abstract

Diamond films grown by plasma chemical vapor deposition techniques display a fairly low resistivity (∼106 Ω cm). Heat treating the films causes an increase in the resistivity by up to six orders of magnitude. The low resistivity of the as-grown films is postulated to be due to hydrogen passivation of traps in the films. Annealing causes dehydrogenation resulting in the electrical activation of deep traps with an attendant increase in the resistivity. This mechanism has been confirmed by an observed reduction of the resistivity of the heat-treated films when they are subjected to a plasma hydrogen treatment.

Ultrawide‐Bandgap Semiconductors: Research Opportunities and Challenges

“…Early studies established that air adsorbates could lead to a two-dimensional hole gas (2DHG) with a sheet charge density in the 10 14 cm −2 range. [113] While these air-exposed surfaces are notably unstable, lateral metal-oxide-semiconductor fieldeffect-transistor (MOSFET) devices have now been fabricated with atomic-layer-deposited (ALD) dielectric layers, as illustrated in Figure 5. These have exhibited sheet charge densities greater than 10 13 cm −2 , stability to ≈400 °C, and high-voltage and high-frequency operation.…”

Diamond growth by chemical vapour deposition

“…As-grown CVD diamond surfaces, grown under hydrogen-rich atmospheres, also show p-type surface conductivity due to the termination of the dangling bonds with hydrogen atoms [92] and have been widely used to fabricate planar devices operating at room temperature [93].…”

Surface band bending and electron affinity as a function of hole accumulation density in surface conducting diamond

“…[1][2][3] This kind of SC is favored by the negative electron affinity ͑NEA͒, , of H-terminated diamond. 4 The NEA lowers the ionization potential of diamond, I = E GAP + , so that surface adsorbates with sufficiently high electron affinity promote charge transfer of electrons from the diamond valence band into the lowest unoccupied molecular orbital of the adsorbate layer leaving holes in the diamond valence band behind; this is known as surface transfer doping.…”