9 research outputs found
\u3cem\u3eIn Situ\u3c/em\u3e Hall-Effect System for Real-Time Electron-Irradiation Studies
A unique system capable of taking in situ Hallâeffect measurements during electron irradiation has been developed. The key element is a small, powerful rareâearth magnet. Measurements can be taken while the electron beam is on, resulting in a considerable time savings and eliminating problems associated with mounting and demounting the sample. High resolution electron concentration and mobility versus fluence data are quickly and easily obtained, making possible detailed defect production rate studies as functions of energy and flux
Electron-Beam Modification of GaAs Surface-Potential - Measurement of Richardson Constant
The surface potential of GaAs is strongly modified in the presence of a highâenergy electron beam due to the creation of electronâhole pairs in the depletion region and the subsequent drift of the holes to the surface where they neutralize surface states. This effect is modeled in terms of a parameter K=AâT2/Ib(dE/dz)Ρ, where Ib is the beam current density, Aâ is the effective Richardson constant, dE/dz is the beam energy loss per unit length, and Ρâ1 is the average energy required to create an electronâhole pair. For the sample studied here, an 0.25âÎźm layer with nâ3Ă1017 cmâ3, we obtain a value Kâ(7.5Âą0.8)Ă104 cm at T=296 K and Ib=0.33 ÎźA/cm2, which gives Aââ0.44 A/cm2âK2. Although this value of Aâ is much lower than the theoretical estimate of 8 A/cm2âK2, it is in good agreement with other recent results
\u3cem\u3eIn Situ\u3c/em\u3e Hall-Effect System for Real-Time Electron-Irradiation Studies
A unique system capable of taking in situ Hallâeffect measurements during electron irradiation has been developed. The key element is a small, powerful rareâearth magnet. Measurements can be taken while the electron beam is on, resulting in a considerable time savings and eliminating problems associated with mounting and demounting the sample. High resolution electron concentration and mobility versus fluence data are quickly and easily obtained, making possible detailed defect production rate studies as functions of energy and flux
\u3cem\u3eIn Situ\u3c/em\u3e Hall-Effect System for Real-Time Electron-Irradiation Studies
A unique system capable of taking in situ Hallâeffect measurements during electron irradiation has been developed. The key element is a small, powerful rareâearth magnet. Measurements can be taken while the electron beam is on, resulting in a considerable time savings and eliminating problems associated with mounting and demounting the sample. High resolution electron concentration and mobility versus fluence data are quickly and easily obtained, making possible detailed defect production rate studies as functions of energy and flux