Chemical Vapor Deposition of α-Boron Layers on Silicon for Controlled Nanometer-Deep p + n Junction Formation

Sarubbi, F.; Scholtes, T.L.M.; Nanver, L.K.

doi:10.1007/s11664-009-1018-6

Cited by 75 publications

(57 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, these properties also make it an attractive process for creating junctions on silicon nanowires and advanced CMOS (complementary metal-oxide-semiconductor) transistors including source/drain in p-type FinFETs. 6,7 These applications require a sub-3-nm thick layer to avoid excess series resistance through the high-resistivity PureB layer.…”

mentioning

confidence: 99%

“…As Sarubbi et al 7 mentioned, in the first seconds of exposure to diborane, boron atoms deposit via interaction with silicon surface sites and the coverage of the deposited layer can grow to exceed 1 ML. After this stage, the boron atoms will be deposited on a closed PureB surface.…”

mentioning

confidence: 99%

“…10 To obtain smooth layers in all cases where the boron-on-boron deposition rate is to be determined, the initial deposition is performed at 700 C, at which temperature complete (monolayer) B coverage of the Si is readily achieved. 7 Subsequently, a series of thicker layers are deposited at the temperature to be investigated. The sheet resistance of some of the PureB layers was determined by using the method described by Sarubbi et al 7 In Fig.…”

mentioning

confidence: 99%

“…7 Subsequently, a series of thicker layers are deposited at the temperature to be investigated. The sheet resistance of some of the PureB layers was determined by using the method described by Sarubbi et al 7 In Fig. 2, Arrhenius plots of the deposition rate (DR) of the PureB layers is shown for two different diborane partial pressures P high and P low that are 3.39 and 1.7 mTorr, respectively.…”

mentioning

confidence: 99%

See 3 more Smart Citations

Temperature dependence of chemical-vapor deposition of pure boron layers from diborane

2012

View full text Add to dashboard Cite

Surface reaction mechanisms are investigated to determine the activation energies of pure boron (PureB) layer deposition at temperatures from 350 C to 850 C when using chemical-vapor deposition from diborane in a commercial Si/SiGe epitaxial reactor with either hydrogen or nitrogen as carrier gas. Three distinguishable regions are identified to be related to the dominance of specific chemical reaction mechanisms. Activation energies in H 2 are found to be 28 kcal/mol below 400 C and 6.5 kcal/mol from 400 C to 700 C. In N 2 , the value decreases to 2.1 kcal/mol for all temperatures below 700 C. The rate of hydrogen desorption is decisive for this behavior. Pure boron (PureB) layer depositions have in recent years been applied for creating the p þ -region of extremely shallow, less than 10-nm deep, silicon p þ n junction diodes for a number of leading-edge device applications. 1 Particularly impressive performance has been achieved for the application to bulk-Si photodiodes for detecting low penetration-depth beams. [2][3][4][5] Ideal diode characteristics have been achieved for deposition temperatures in the 400 C-700 C range. The option of depositing at temperatures below $500 C, which together with the fact that the deposition is conformal and highly selective to Si, makes PureB technology highly compatible with amorphous-/polysilicon-/ crystalline-silicon thin-film device processing. Moreover, these properties also make it an attractive process for creating junctions on silicon nanowires and advanced CMOS (complementary metal-oxide-semiconductor) transistors including source/drain in p-type FinFETs. 6,7 These applications require a sub-3-nm thick layer to avoid excess series resistance through the high-resistivity PureB layer.In the present work, the deposition is performed in a commercial Si/SiGe epitaxial reactor by exposing the Si surface to diborane (B 2 H 6 ). At 700 C, in the first few seconds of exposure, the boron atoms interact with the Si surface sites to quickly build up something like an atomic layer plane, and upon further deposition, the boron coverage readily exceeds one monolayer (1 ML). After this, the boron atoms will be deposited on a full PureB surface, which is a process that has a much slower, well-controlled deposition rate. In the past, it has been shown that less than 2-nm-thick layers can be deposited with good reliability and uniformity by a suitable adjustment of deposition parameters such as deposition time, temperature, partial pressures, and flow rates. 8 In this paper, an investigation is presented of the surface reaction mechanisms and activation energies of PureB layer deposition in the temperature range of 350 C to 850 C. At the lower temperatures, the carrier gas has a large influence on the ability to create the first full boron coverage of the Si. Nevertheless, by first creating a full PureB coverage at 700 C, which is smooth and uniform, and then proceeding with the low-temperature depositions, the boron-on-boron activation energies could be determined over the whole temp...

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Temperature dependence of chemical-vapor deposition of pure boron layers from diborane

2012

View full text Add to dashboard Cite

show abstract

“…In the simulations, based on experimental results for PureB diodes from 700 • C boron depositions [37], the PureB p + region is simulated as a high-doped region with peak concentration at the surface of 2 × 10 19 cm −3 and a Gaussian doping profile. The pn-junction depth of the boron-diffused region for N D = 5 × 10 11 cm −3 is assumed to be 50 nm.…”

Section: Electrostatic Optimization Of the Tdd Structurementioning

confidence: 99%

Silicon Drift Detectors with the Drift Field Induced by PureB-Coated Trenches

2016

View full text Add to dashboard Cite

Junction formation in deep trenches is proposed as a new means of creating a built-in drift field in silicon drift detectors (SDDs). The potential performance of this trenched drift detector (TDD) was investigated analytically and through simulations, and compared to simulations of conventional bulk-silicon drift detector (BSDD) configurations. Although the device was not experimentally realized, the manufacturability of the TDDs is estimated to be good on the basis of previously demonstrated photodiodes and detectors fabricated in PureB technology. The pure boron deposition of this technology allows good trench coverage and is known to provide nm-shallow low-noise p + n diodes that can be used as radiation-hard light-entrance windows. With this type of diode, the TDDs would be suitable for X-ray radiation detection down to 100 eV and up to tens of keV energy levels. In the TDD, the drift region is formed by varying the geometry and position of the trenches while the reverse biasing of all diodes is kept at the same constant voltage. For a given wafer doping, the drift field is lower for the TDD than for a BSDD and it demands a much higher voltage between the anode and cathode, but also has several advantages: it eliminates the possibility of punch-through and no current flows from the inner to outer perimeter of the cathode because a voltage divider is not needed to set the drift field. In addition, the loss of sensitive area at the outer perimeter of the cathode is much smaller. For example, the simulations predict that an optimized TDD geometry with an active-region radius of 3100 µm could have a drift field of 370 V/cm and a photo-sensitive radius that is 500-µm larger than that of a comparable BSDD structure. The PureB diodes on the front and back of the TDD are continuous, which means low dark currents and high stability with respect to leakage currents that otherwise could be caused by radiation damage. The dark current of the 3100-µm TDD will increase by only 34% if an interface trap concentration of 10 12 cm −2 is introduced to approximate the oxide interface degradation that could be caused during irradiation. The TDD structure is particularly well-suited for implementation in multi-cell drift detector arrays where it is shown to significantly decrease the cross-talk between segments. The trenches will, however, also present a narrow dead area that can split the energy deposited by high-energy photons traversing this dead area. The count rate within a cell of a radius = 300 µm in a multi-cell TDD array is found to be as high as 10 Mcps.

show abstract

Radiation Detectors with Semiconductor Absorbers

2022

Nuclear Electronics With Quantum Cryogenic Detectors

View full text Add to dashboard Cite

Chemical Vapor Deposition of α-Boron Layers on Silicon for Controlled Nanometer-Deep p + n Junction Formation

Cited by 75 publications

References 19 publications

Temperature dependence of chemical-vapor deposition of pure boron layers from diborane

Temperature dependence of chemical-vapor deposition of pure boron layers from diborane

Silicon Drift Detectors with the Drift Field Induced by PureB-Coated Trenches

Radiation Detectors with Semiconductor Absorbers

Contact Info

Product

Resources

About