Measurement accuracy analysis of photocarrier radiometric determination of electronic transport parameters of silicon wafers

Review of Scientific Instruments

2005

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Articles you may be interested inPhotocarrier radiometry of ion-implanted and thermally annealed silicon wafers with multiple-wavelength excitationsThe influence of vignetting on the photocarrier radiometry ͑PCR͒ measurements of semiconductor wafers has been investigated both theoretically and experimentally by analyzing the vignetting effect on the PCR amplitude and on the frequency dependence of the PCR amplitude and phase. The vignetting effect significantly reduces the PCR amplitude and modifies the frequency dependencies that are widely used to extract simultaneously the electronic transport properties ͑that is, the carrier lifetime, the carrier diffusion coefficient, and the front and rear surface recombination velocities͒ of semiconductor wafers. When using the frequency dependence of the PCR signal to determine the transport properties, the effect of vignetting can be accounted for by an "effective detector size"-a reduced detector size determined by the actual detector size and the vignetting effect.

Section: ͑13͒supporting

confidence: 84%

Influence of vignetting on signal analysis of photocarrier radiometry of semiconductor wafers

Shaughnessy

Review of Scientific Instruments

2005

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“…Similarly, the nm-thick i-a-Si:H layer was very thin compared to the CDW wavelength 1 |σ 2 | even at the highest modulation frequency f = 100 kHz (∼µm), which justified reducing the CDW solution at the interface to boundary conditions Eqs. (5) and (6). The best-fitted results show that the values from the meanvalue best-fit computational program are all close to those obtained with the independent statistical best fit program.…”

Section: A Doping Density Dependent Measurementssupporting

confidence: 70%

Optoelectronic transport properties in amorphous/crystalline silicon solar cell heterojunctions measured by frequency-domain photocarrier radiometry: Multi-parameter measurement reliability and precision studies

Zhang

Melnikov

Review of Scientific Instruments

et al. 2015

A theoretical one-dimensional two-layer linear photocarrier radiometry (PCR) model including the presence of effective interface carrier traps was used to evaluate the transport parameters of p-type hydrogenated amorphous silicon (a-Si:H) and n-type crystalline silicon (c-Si) passivated by an intrinsic hydrogenated amorphous silicon (i-layer) nanolayer. Several crystalline Si heterojunction structures were examined to investigate the influence of the i-layer thickness and the doping concentration of the a-Si:H layer. The experimental data of a series of heterojunction structures with intrinsic thin layers were fitted to PCR theory to gain insight into the transport properties of these devices. The quantitative multi-parameter results were studied with regard to measurement reliability (uniqueness) and precision using two independent computational best-fit programs. The considerable influence on the transport properties of the entire structure of two key parameters that can limit the performance of amorphous thin film solar cells, namely, the doping concentration of the a-Si:H layer and the i-layer thickness was demonstrated. It was shown that PCR can be applied to the non-destructive characterization of a-Si:H/c-Si heterojunction solar cells yielding reliable measurements of the key parameters.

“…LIC images can only be obtained up to 2 kHz due to the small camera signal at short exposure times at high frequencies. This upper frequency limit is not enough for separating the resolved transport parameters by multi‐parameter fitting . Therefore, for homodyne LIC, semiconductor samples can be characterized only by their effective lifetime .…”

Section: Resultsmentioning

confidence: 99%

Camera‐based high frequency heterodyne lock‐in carrierographic (frequency‐domain photoluminescence) imaging of crystalline silicon wafers

Sun

Melnikov

Physica Status Solidi (a)

2015

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A heterodyne lock‐in imaging scheme is introduced to overcome NIR camera speed limitations and poor signal‐to‐noise ratios, thereby generating high‐frequency carrierographic imaging up to 10 kHz. A theoretical model was established to investigate the heterodyne signal generation mechanism as well as to extract the major carrier transport parameters by best‐fitting the entire modulation frequency dependence. Good agreement was found between the theoretically predicted and experimentally measured heterodyne amplitude dependence on excitation intensity. A contrast inversion feature in the high‐frequency heterodyne amplitude images was observed. High‐frequency information presents a method for resolving local near‐surface carrier transport parameters from the lumped effective lifetime, thereby providing ac‐diffusion‐length‐controlled depth‐selective/resolved imaging. Heterodyne lock‐in carrierography (LIC) amplitude images of a crystalline silicon wafer at different frequencies.