UMN K100 Run67 - Crystal

The Ge crystal used in USD1 was "No.27 crystal (2014)" fabricated by Dongming Mai's group at USD. A paper desccribing the process of making similar crystals is here. The measured properties of this crystal can be found below.

• Net Impurity vs. Radius \(N_A-N_D \sim 10^{11} cm^{-3}\)
• \(N_D+N_A = 5 \sim 7.5 \times 10^{11} cm^{-3}\)
• \(N_D = 1 \sim 3.5 \times 10^{11} cm^{-3}\)
• \(N_A = \sim 4 \times 10^{11} cm^{-3}\)

"These numbers are estimated values based on impurity distribution in the crystal. We can only use Hall effect measurement to measure the net carrier concentration (NA-ND). To get the absolute amount for each impurity, we need to fit the impurity distribution in whole crystal by impurity segregation equation. The fitted results have some uncertainty." - Guojian Wang (USD)