Generalized analysis of quasi-steady-state and quasi-transient measurements of carrier lifetimes in semiconductors

Nagel, H.; Berge, Christopher; Aberle, Armin G.

doi:10.1063/1.371633

Cited by 309 publications

(141 citation statements)

References 8 publications

Supporting

Mentioning

131

Contrasting

Unclassified

Order By: Relevance

“…A circular ITO target with a composition of In 2 O 3 /SnO 2 : 90/10 weight percent, a diameter of 30 cm and a purity of 99.99 % was utilized and additional oxygen was introduced along with argon during the sputter process, which dosage allows for controlling the density of electrons in the conduction band of the deposited film. The sputter-induced damage of well-passivated lifetime samples was evaluated via photo conductance measured by the Sinton WCT-120 tool operated in generalized mode [13] and quantified by the corresponding iV oc values at one sun illumination averaged for at least two samples. The TOPCon lifetime samples consisted of 200 μm thick n-type silicon FZ wafers with a resistivity of 1 Ωcm (Fig.…”

Section: Methodsmentioning

confidence: 99%

Integrating transparent conductive oxides to improve the infrared response of silicon solar cells with passivating rear contacts

Tutsch

Feldmann

Bivour

et al. 2018

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. This work addresses the development of a transparent conductive oxide (TCO)/metal stack for n-type Si solar cells featuring a tunnel oxide passivating rear contact (TOPCon). While poly-Si based passivating contacts contacted by local fire-through metallization currently show an increased recombination at the metal contacts and a poor infrared (IR) response, we aim to realize a full-area metallization which maintains the high level of surface passivation and avoids IR losses. Some research groups have reported that sputtering TCOs on poly-Si based passivating contacts degrades the surface passivation and unlike the SHJ cells this degradation cannot be cured completely at Tcure ~ 200°C. However, the higher thermal stability of TOPCon allows for higher Tcure of up to 400°C, which can effectively restore the surface passivation. On the other hand, the contact resistivity (ρc) of the TOPCon/ITO/metal contact increased by several orders of magnitude in our test structures during annealing at such high temperatures. Possible reasons like the formation of an interfacial oxide are currently under investigation. Increasing the poly-Si thickness and/or doping mitigated the effect of sputter damage, but this will come at the cost of more parasitic absorption. However, by adapting the sputter and the subsequent annealing process, we were able to realize low damage deposition of ITO (loss in implied Voc ~ 7 mV) on thin, lowly doped poly-Si layers on textured wafers, yielding reasonable contact properties (ρc ~ 40 mΩcm² of the whole rear contact stack).

show abstract

Section: Methodsmentioning

confidence: 99%

Integrating transparent conductive oxides to improve the infrared response of silicon solar cells with passivating rear contacts

Tutsch

Feldmann

Bivour

et al. 2018

AIP Conference Proceedings

View full text Add to dashboard Cite

show abstract

“…The second method, i.e., QSSPC, measures the balance between generation and recombination when a quasisteady-state illumination is maintained. The generalized lifetime [8] is then extracted as…”

Section: Theoretical Principlesmentioning

confidence: 99%

A Contactless Method for Determining the Carrier Mobility Sum in Silicon Wafers

Rougieux

Zheng

Thiboust

et al. 2012

IEEE J. Photovoltaics

View full text Add to dashboard Cite

Abstract-In this paper, we present a new method to determine the simultaneous injection and temperature dependence of the sum of the majority and minority carrier mobilities in silicon wafers. The technique is based on combining transient and quasi-steadystate photoconductance measurements. It does not require a full device structure or contacting but only adequate surface passivation. The mobility dependence on both carrier injection level and temperature, as measured on several test samples, is discussed and compared with well-known mobility models. The potential of this method to measure the impact of dopant concentration, compensation ratio, injection level, and temperature on the mobility is demonstrated.

show abstract

“…Following this, the samples were consecutively subjected to isothermal annealing treatments in air for prolonged times t ann . The value for the effective carrier lifetime eff of the samples was measured with a Sinton Consulting WCT-100 quasi-steady-state photoconductance system, 17 operated either in the so-called generalized, 18 or transient mode. For this, the annealing treatments were shortly interrupted.…”

mentioning

confidence: 99%

Stretched-exponential a-Si:H∕c-Si interface recombination decay

Wolf¹,

Olibet²,

Ballif³

2008

Applied Physics Letters

133

113

View full text Add to dashboard Cite

The electronic properties of hydrogenated amorphous silicon ͑a-Si: H͒ relax following stretched exponentials. This phenomenon was explained in the past by dispersive hydrogen diffusion, or by retrapping included hydrogen motion. In this letter, the authors report that the electronic passivation properties of intrinsic a-Si: H/crystalline silicon ͑c-Si͒ interfaces relax following a similar law. Carrier injection dependent a-Si: H / c-Si interface recombination calculations suggest this originates from amphoteric interface state ͑or Si dangling bond͒ reduction, rather than from a field effect. These findings underline the similarity between a-Si: 3 Alternatively, c-Si surface dangling bond passivation may also be obtained by deposition of intrinsic hydrogenated amorphous silicon ͑a-Si: H͒ films. 4 As such films can, in addition, be doped relatively easily, they allow for the fabrication of electronically abrupt a-Si: H / c-Si heterojunctions.5 Since direct deposition of such doped films on c-Si can result in poor interface properties, typically, a few nanometer thin intrinisic a-Si: H͑i͒ buffer layer is inserted in between for a-Si: H / c-Si heterostructure solar cell fabrication.6 Impressive large area ͑Ͼ100 cm 2 ͒ energy conversion efficiencies ͑Ͼ22% ͒ have been reported for such devices.7 For this, atomically sharp a-Si: H / c-Si interfaces, i.e., where no epitaxial Si ͑epi-Si͒ film was grown on the wafer during film deposition, are considered to be essential. 8 This can be monitored in real time by various optical probes.9,10 On a related note, the excellent a-Si: H / c-Si interface passivation properties may also offer an explanation why surrounding a-Si: H tissue is crucial for device-grade microcrystalline Si.11 Nevertheless, the relation between processing parameters and the physical mechanism underlying the a-Si: H / c-Si interface passivation is not yet fully understood.Previously it was suggested that low-temperature annealing is beneficial for the interface passivation quality, provided that neither epi-Si at the interface 12 nor boron-doped overlayer 13,14 is present. In this letter, we show that under these conditions electronic passivation relaxation can be accurately described by stretched exponentials. It is observed that even moderate temperature ͑ഛ 180°C͒ annealing can yield an extremely low interface recombination activity. Carrier injection dependent recombination calculations suggest that the origin of this phenomenon is related to dangling bond reduction at the interface, rather than to a field effect.Consequently, similar to the SiO 2 / c-Si interface, 15 also here, a strong analogy between the nature of the defects present at the a-Si: H͑i͒ / c-Si interface and those in the a-Si: H͑i͒ bulk may possibly exist.For the experiments, 300 m thick ϳ3.0 ⍀ cm phosphorus-doped high quality float zone ͑100͒ FZ-Si wafers were used. Both substrate surfaces were mirror polished to eliminate the influence of substrate surface roughness on the passivation properties. 16 Surface cleaning simply consisted o...

show abstract

Generalized analysis of quasi-steady-state and quasi-transient measurements of carrier lifetimes in semiconductors

Cited by 309 publications

References 8 publications

Integrating transparent conductive oxides to improve the infrared response of silicon solar cells with passivating rear contacts

Integrating transparent conductive oxides to improve the infrared response of silicon solar cells with passivating rear contacts

A Contactless Method for Determining the Carrier Mobility Sum in Silicon Wafers

Stretched-exponential a-Si:H∕c-Si interface recombination decay

Contact Info

Product

Resources

About