Activation of Beryllium-Implanted GaN by Two-Step Annealing

AbstractFor the first time, p-type doping through beryllium implantation in gallium nitride was achieved by using a new annealing process, in which the sample was first annealed in forming gas (12% H2 and 88% N2), followed by annealing in pure nitrogen. Variable temperature Hall measurements showed that sheet hole concentrations of the annealed samples were about 1×1013 cm−2 with low hole mobilities. An ionization energy of 127 meV was estimated with a corresponding activation efficiency of ∼ 100%. SIMS results revealed a relationship between the enhanced diffusion of Be and activation of the acceptors.

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Акцепторное легирование мышьяком при осаждении слоев CdTe из диметилкадмия и диизопропилтеллура

Физика и техника полупроводников ◽

10.21883/ftp.2021.01.50377.9514 ◽

2021 ◽

Vol 55 (1) ◽

pp. 9

Author(s):

В.С. Евстигнеев ◽

А.В. Чилясов ◽

А.Н. Моисеев ◽

С.В. Морозов ◽

Д.И. Курицын

Keyword(s):

Ionization Energy ◽

Hole Concentration ◽

Arsenic Concentration ◽

Chemical Vapor ◽

Argon Flow ◽

Gaas Substrates ◽

Activation Efficiency ◽

Donor Acceptor ◽

P Type ◽

Arsenic Incorporation

The incorporation and activation of arsenic from tris(dimethylamino)arsine in CdTe layers grown by metalorganic chemical vapor deposition with dimethylcadmium and diisopropyltellurium on GaAs substrates are investigated. Arsenic incorporation into CdTe to depend on the crystallographic orientation of the layers and increases in the order (111)B<(100)<(310). Arsenic concentration in the CdTe layers is proportional to the tris(dimethylamino)arsine flow rate to the power of 1.4 and an increase with decrease of the diisopropyltellurium/dimethylcadmium ratio from 1.4 to 0.5. The as-grown CdTe:As layers had p-type conductivity with arsenic and hole concentrations of 1·1017–7·1018 and 2.7·1014–4.6·1015 cm–3, respectively, but the arsenic activation efficiency not exceeding 0.3%. After annealing in argon flow (250–450 ° C) the highest hole concentration and arsenic activation efficiency were 1·1017 cm–3 and ~4.5 % respectively. The ionization energy of arsenic determined from the temperature dependence of the hole concentration was in the range of 98–124 meV. Low-temperature photoluminescence spectra of the layers showed an emission peak with energy of 1.51 eV, which can be attributed to donor-acceptor recombination, where the acceptor is AsTe with ionization energy about 90 meV.

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Achievement of low p-type carrier concentration for MOCVD growth HgCdTe without an annealing process

Journal of Crystal Growth ◽

10.1016/s0022-0248(97)00620-9 ◽

1998 ◽

Vol 184-185 (1-2) ◽

pp. 1228-1231

Author(s):

K Matsushita

Keyword(s):

Carrier Concentration ◽

Annealing Process ◽

Mocvd Growth ◽

P Type

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Stable Cu2O Photoelectrodes by Reactive Ion Beam Sputter Deposition

Advances in Materials Science and Engineering ◽

10.1155/2018/3792672 ◽

2018 ◽

Vol 2018 ◽

pp. 1-7

Author(s):

Ching-Hsiu Chen ◽

Assamen Ayalew Ejigu ◽

Liang-Chiun Chao

Keyword(s):

Electrode Materials ◽

Variable Temperature ◽

Ion Beam ◽

Sputter Deposition ◽

Flow Rates ◽

Vacancy Defects ◽

Photoluminescence Study ◽

P Type ◽

Quartz Substrates ◽

Ion Beam Sputter Deposition

Cu2O has been deposited on quartz substrates by reactive ion beam sputter deposition. Experimental results show that by controlling argon/oxygen flow rates, both n-type and p-type Cu2O samples can be achieved. The bandgap of n-type and p-type Cu2O were found to be 2.3 and 2.5 eV, respectively. The variable temperature photoluminescence study shows that the n-type conductivity is due to the presence of oxygen vacancy defects. Both samples show stable photocurrent response that photocurrent change of both samples after 1,000 seconds of operation is less than 5%. Carrier densities were found to be 1.90 × 1018 and 2.24 × 1016 cm−3 for n-type and p-type Cu2O, respectively. Fermi energies have been calculated, and simplified band structures are constructed. Our results show that Cu2O is a plausible candidate for both photoanodic and photocathodic electrode materials in photoelectrochemical application.

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12 kV 4H-SiC p-IGBTs with Record Low Specific On-Resistance

Materials Science Forum ◽

10.4028/www.scientific.net/msf.600-603.1187 ◽

2008 ◽

Vol 600-603 ◽

pp. 1187-1190 ◽

Cited By ~ 22

Author(s):

Q. Jon Zhang ◽

Charlotte Jonas ◽

Joseph J. Sumakeris ◽

Anant K. Agarwal ◽

John W. Palmour

Keyword(s):

Carrier Lifetime ◽

Drift Region ◽

Gate Bias ◽

Enhancement Layer ◽

Channel Mobility ◽

Dc Characteristics ◽

Blocking Voltage ◽

High Carrier ◽

P Type ◽

First Time

DC characteristics of 4H-SiC p-channel IGBTs capable of blocking -12 kV and conducting -0.4 A (-100 A/cm2) at a forward voltage of -5.2 V at 25°C are demonstrated for the first time. A record low differential on-resistance of 14 mW×cm2 was achieved with a gate bias of -20 V indicating a strong conductivity modulation in the p-type drift region. A moderately doped current enhancement layer grown on the lightly doped drift layer effectively reduces the JFET resistance while maintains a high carrier lifetime for conductivity modulation. A hole MOS channel mobility of 12.5 cm2/V-s at -20 V of gate bias was measured with a MOS threshold voltage of -5.8 V. The blocking voltage of -12 kV was achieved by Junction Termination Extension (JTE).

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Ultra-Shallow Junctions by Ion Implantation and Rapid Thermal Annealing: Spike-Anneals, Ramp Rate Effects

MRS Proceedings ◽

10.1557/proc-568-19 ◽

1999 ◽

Vol 568 ◽

Cited By ~ 17

Author(s):

Aditya Agarwal ◽

Hans-J. Gossmann ◽

Anthony T. Fiory

Keyword(s):

Thermal Annealing ◽

Rapid Thermal Annealing ◽

Driving Forces ◽

Recent Experimental Data ◽

Enhanced Diffusion ◽

Temperature Ramp ◽

Rate Effects ◽

Low Energies ◽

Ultra Shallow Junctions ◽

P Type

ABSTRACTOver the last couple of years rapid thermal annealing (RTA) equipment suppliers have been aggressively developing lamp-based furnaces capable of achieving ramp-up rates on the order of hundreds of degrees per second. One of the driving forces for adopting such a strategy was the experimental demonstration of 30nm p-type junctions by employing a ramp-up rate of ≈400°C/s. It was subsequently proposed that the ultra-fast temperature ramp-up was suppressing transient enhanced diffusion (TED) of boron which results from the interaction of the implantation damage with the dopant. The capability to achieve very high temperature ramp-rates was thus embraced as an essential requirement of the next generation of RTA equipment.In this paper, recent experimental data examining the effect of the ramp-up rate during spike-and soak-anneals on enhanced diffusion and shallow junction formation is reviewed. The advantage of increasing the ramp-up rate is found to be largest for the shallowest, 0.5-keV, B implants. At such ultra-low energies (ULE) the advantage arises from a reduction of the total thermal budget. Simulations reveal that a point of diminishing return is quickly reached when increasing the ramp-up rate since the ramp-down rate is in practice limited. At energies where TED dominates, a high ramp-up rate is only effective in minimizing diffusion if the implanted dose is sufficiently small so that the TED can be run out during the ramp-up portion of the anneal; for larger doses, a high ramp-up rate only serves to postpone the TED to the ramp-down duration of the anneal. However, even when TED is minimized at higher implant energies via high ramp-up rates, the advantage is unobservable due to the rather large as-implanted depth. It appears then that while spike anneals allow the activation of ULE-implanted dopants to be maximized while minimizing their diffusion the limitation imposed by the ramp-down rate compromises the advantage of very aggressive ramp-up rates.

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An effective and efficient approach to p-type AlN by Be2:O codoping from first-principles calculations

Modern Physics Letters B ◽

10.1142/s0217984916502572 ◽

2016 ◽

Vol 30 (20) ◽

pp. 1650257

Author(s):

Meng Zhao ◽

Wenjun Wang ◽

Jun Wang ◽

Junwei Yang ◽

Weijie Hu ◽

...

Keyword(s):

First Principles ◽

Ionization Energy ◽

Hole Concentration ◽

Valence Band Maximum ◽

First Principles Calculations ◽

Mutual Compensation ◽

Efficient Approach ◽

P Type ◽

Codoping Method

Various Be:O-codoped AlN crystals have been investigated via first-principles calculations to evaluate the role of the different combinations in effectively and efficiently inducing p-type carriers. It is found that the O atom is favored to bond with two Be atoms. The formed Be2:O complexes decrease the acceptor ionization energy to 0.11 eV, which is 0.16 eV lower than that of an isolated Be in AlN, implying that the hole concentration could probably be increased by 2–3 orders of magnitude. The electronic structure of Be2:O-codoped AlN shows that the lower ionization energy can be attributed to the interaction between Be and O. The Be–O complexes, despite failing to induce p-type carriers for the mutual compensation of Be and O, introduce new occupied states on the valence-band maximum (VBM) and hence the energy needed for the transition of electrons to the acceptor level is reduced. Thus, the Be2:O codoping method is expected to be an effective and efficient approach to realizing p-type AlN.

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Self- and Dopant Diffusion in Extrinsic Boron Doped Isotopically Controlled Silicon Multilayer Structures

MRS Proceedings ◽

10.1557/proc-719-f13.11 ◽

2002 ◽

Vol 719 ◽

Cited By ~ 9

Author(s):

Ian D. Sharp ◽

Hartmut A. Bracht ◽

Hughes H. Silvestri ◽

Samuel P. Nicols ◽

Jeffrey W. Beeman ◽

...

Keyword(s):

Multilayer Structure ◽

Secondary Ion Mass Spectrometry ◽

Diffusion Processes ◽

Quantitative Description ◽

Multilayer Structures ◽

Dopant Diffusion ◽

Enhanced Diffusion ◽

Self Diffusion ◽

Boron Doped ◽

P Type

AbstractIsotopically controlled silicon multilayer structures were used to measure the enhancement of self- and dopant diffusion in extrinsic boron doped silicon. 30Si was used as a tracer through a multilayer structure of alternating natural Si and enriched 28Si layers. Low energy, high resolution secondary ion mass spectrometry (SIMS) allowed for simultaneous measurement of self- and dopant diffusion profiles of samples annealed at temperatures between 850°C and 1100°C. A specially designed ion-implanted amorphous Si surface layer was used as a dopant source to suppress excess defects in the multilayer structure, thereby eliminating transient enhanced diffusion (TED) behavior. Self- and dopant diffusion coefficients, diffusion mechanisms, and native defect charge states were determined from computer-aided modeling, based on differential equations describing the diffusion processes. We present a quantitative description of B diffusion enhanced self-diffusion in silicon and conclude that the diffusion of both B and Si is mainly mediated by neutral and singly positively charged self-interstitials under p-type doping. No significant contribution of vacancies to either B or Si diffusion is observed.

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