Measuring doping profiles of silicon detectors with a custom-designed probe station

Abstract

Silicon detectors are often used in High Energy Physics (HEP) experiments as tracking and vertexing devices. Many scientific institutes are equipped with setups able to electrically characterize those detectors e.g. for quality assurance reasons. Such probe stations can be easily extended to measure resistivities and doping profiles in the bulk material and in doped regions by using the Spreading Resistance Probe (SRP) technique. After an introduction to the method, this paper describes how an existing probe station, that has been used for electrical measurements on strip detectors, has been modified to perform SRP measurements. The presented results prove that the method is reliable and capable of characterizing doping regions as thin as one micron. Beside profiling implants, SRP measurements have the potential to deliver the basis for investigations of bulk material defects in heavily irradiated samples.

Planar sensors for future Vertex and Tracking Detectors

“…Several options are available like a moderately pdoped layer (p-spray) or highly p-doped structures surrounding the strips in different geometries (p-stop). Figure 8 [25]. T-CAD simulations could not reproduce the good isolation properties with the low doping concentrations and a surface charge density of 5 · 10 11 cm −2 expected for a fluence of 5 · 10 14 n eq cm −2 .…”

Experimental study of different silicon sensor options for the upgrade of the CMS Outer Tracker

“…The boron and phosphorus bulk doping concentrations are around 3 × 10 12 cm −3 for the floatzone and 4-5 × 10 12 cm −3 for the MCz sensors. The doping concentration parameters measured by spreading resistance profiling (SRP) [12] are listed in table 2. SRP is a technique used to measure resistivity as a function of depth in semiconductors.…”

Interplay Between Statistical Variability and Reliability in Contemporary pMOSFETs: Measurements Versus Simulations

“…6 shows the 1-D plot of the inverse of spread resistance at the center of the channel. This is proportional to the doping value, but a proper conversion factor would require a careful experimental calibration procedure, as reported in [32]. The trend of V T roll-off is a first important benchmark step to check the validity of the doping profile obtained by process simulation.…”