Esidor Ntsoenzok

French National Centre for Scientific Research | CNRS · CEMHTI

The highest power conversion efficiency (PCE) of perovskite solar cells (PSCs) employed the regular (n-i-p) architecture which has PCE of over 22%, but this is achieved by a thick layer of mesoporous TiO2 which require high-temperature post-deposition annealing. In this work, we employed the inverted planar (n-i-p) perovskite solar cell architectur...

The highest power conversion efficiency (PCE) of perovskite solar cells (PSCs) employed the regular (n-i-p) architecture which has PCE of over 22%, but this is achieved by a thick layer of mesoporous TiO2 which require high-temperature post-deposition annealing. In this work, we employed the inverted planar (n-i-p) perovskite solar cell architectur...

We studied the distribution of implanted Xe in amorphous SiO2. Our results clearly showed that Xe profile is energy and fluence dependent. By varying ion energy from 50 to 300 keV, we found that its thermal out-diffusion is very conventional for the first two energies and unexpected for the highest energy. In that last case Xe main peak increases w...

The gettering capacity of cavities towards metals is exploited in order to purify mc-Si wafers. The purification sequence includes: i) cavity creation on the wafer surface by plasma immersion ion implantation (PIII) of hydrogen; ii) high-temperature annealing to promote cavity growth and trapping of metal impurities by chemisorption at the cavity s...

Multi-implantations of He ions were performed on Si samples with (111) or (100) surface orientation in the kiloelectron volt (keV) energy range. The fluencies were chosen to keep the local He concentration constant and above the threshold to get nanocavities upon annealing. Small-angle X-ray scattering (SAXS) experiments were carried out, for the f...

To reduce the cost of silicon-based solar grade wafers, it is mandatory to set up a process able to both reduce the total amount of impurities which are detrimental for photovoltaic efficiency and to passivate the extended defects such as dislocations and grain boundaries always present in such materials. In this context the use of a low cost techn...

Undoped and Nd-doped titanium dioxide anatase and rutile films have been grown by pulsed-laser deposition at 700 °C under 0.1 mbar O2. By selecting adequate substrates, TiO2 films doped with 1, 2 or 5 at.% Nd were grown and constituted with polycrystalline rutile, highly oriented (2 0 0) rutile film, or oriented (0 0 4) anatase. An UV to NIR photon...

Creation of nanocativies in silicon has numerous potentialities for microelectronics, optoelectronics and photovoltaics. Indeed, nanocavities can getter detrimental transient metal impurities, they are used to smartly exfoliate thin slides of wafers used for silicon on insulator technology and eventually, nanocavities in pseudo substrate can contro...

To reduce the cost of silicon-based solar grade wafers, it is mandatory to set up a process able to both reduce the total amount of impurities which are detrimental for photovoltaic efficiency and to passivate the extended defects such as dislocations and grain boundaries always present in such materials. In this context the use of a low costs tech...

(111)- and (100)-oriented Si samples were implanted with Si ions at 1 MeV to a dose of 1 × 10 cm and with 5 × 10 He cm at 10 keV or 50 keV and eventually annealed in the 800–1000°C temperature range. Sample characterisation was carried out by cross-section transmission electron microscopy, positron annihilation spectroscopy and nuclear reaction ana...

P+NN+ silicon rectifiers have been irradiated by protons and alpha particles. DLTS and reverse recovery time (the so called TRR) measurements were performed in both as-irradiated and annealed (400°C) samples. The evolution of implantation induced-centers with the annealing is not the same when using the two particles. For example, the concentration...

Commercial n-type 4H-SiC wafers were implanted with doses of MeV alpha particles, high enough to cause majority carrier modification. Analysis of infrared reflectivity spectra shows that the implanted crystals can be divided into three layers: a surface layer of about 30 nm followed by a compensation layer where the energy transfer of the incident...

Thermally-grown 220nm-thick silicon oxide layers were implanted at room temperature with 300keV Xe at doses ranging from 0.5 to 5x1016Xe/cm2. As-implanted samples exhibit bubbles in silicon oxide for all doses. Annealing at T≤400°C results in the disappearance of bubbles from SiO2 layer for the dose of 1x1016Xe/cm2. But for the higher doses of 3.5...

He implantation followed by thermal anneal is a well-established technique for creating layers or bands of cavities in silicon. This process is a consequence of the interaction between He and ion-implant-induced vacancies. Applications of such cavity layers include gettering and localized minority carrier lifetime control, and compliant substrates...

Thermally grown amorphous SiO2 was implanted at room temperature with heavy noble gases Kr and Xe in order to create cavities in the oxide and increase its porosity. The implantation energies were chosen in order to have the same implantation depth for both ions. Although both ions induce bubbles in amorphous SiO2, bubble size and spatial distribut...

The photoluminescence of silver nanoparticles glasses obtained by ionic exchange and annealing is investigated for various ionic exchange times. These glasses are prepared by immersion of silicate glass samples in a molten salt bath of molar concentration 10% AgNO3 in NaNO3 at T = 320 °C. Scanning electron microscopy measurement in electron diffrac...

We performed RBS, infrared (IR) and C–V measurements in order to follow the evolution of Xe, bubbles/cavities and other defects (with a focus on NBOHC: non-bridging oxygen hole center) and dielectric constant (k), in high dose Xe implantation in SiO2. As-implanted sample provides the lowest value of k which increases with post thermal annealing. In...

He, Si and B implantation are successively combined in order to produce ultra shallow junctions (USJs). Si is implanted at 180 keV to create a ‘vacancy-rich’ layer. Such a layer is however followed by a deeper interstitial rich one. He implantation is performed at a dose high enough (5 × 1016 cm− 2) to create a cavity layer in Si sample. Eventually...

He, Si and B implantation are successively combined in order to produce ultra shallow junctions (USJs). Si is implanted at 180 keV to create a 'vacancy-rich' layer. Such a layer is however followed by a deeper interstitial rich one. He implantation is performed at a dose high enough (5 × 10 16 cm − 2) to create a cavity layer in Si sample. Eventual...

Amorphous SiO2 layers grown thermally and by chemical vapour deposition (CVD) were implanted at room temperature with Kr ions in an attempt to form bubbles in the oxide layer. Cross-sectional Transmission Electron Microscopy studies show that Kr implantation induces bubbles in both type of SiO2. However, the bubble distribution and size depend stro...

The reduction of the dielectric constant of the inter-metal dielectric is a key task for realizing high performances IC devices. In this work ion implantation is proposed as a novel method to reduce the dielectric properties of SiO2. Thermally grown SiO2 on silicon was implanted by Xe at 300 keV and a fluence of 5×1016 at/cm2. The dielectric consta...

Thermally grown SiO2 was implanted at room temperature with 220 keV Kr in order to generate bubbles/cavities in the sample. The formation and thermal stability of these bubbles/cavities is studied in this work. Transmission Electron Microscopy (TEM), Rutherford Backscattering Spectrometry (RBS) and Positron Annihilation Spectroscopy (PAS) were used...

High resolution transmission electron microscopy observations show for the first time the presence of two orientations of pure silver precipitates in nanocavities induced in bulk silicon by implantation at 1.6 MeV with a dose of 5×1016 He+ cm−2 and a two hour annealing at 1050°C. These precipitates were called A and B to refer to the two well-known...

Implantation of heavy inert gas ions such as Kr and Xe are found to form nanometer-size bubbles/cavities in thermally grown silicon dioxide. Implantation energies were chosen to produce the same projected range R-p similar to 125 nm for the two ions. The bubble/cavity distribution and size are found to be ion-mass-dependent. After thermal annealing...

Thermally grown silicon oxide layer was implanted at room temperature with 300keV Xe at fluences ranging from 0.5 to 5x10$^16$Xe/cm$^2$. Bubbles created after Xe-implantation provided a low-k silicon oxide that has potential use as a dielectric material for interconnects in Si integrated circuits. Transmission Electron Microscopy (TEM), Rutherford...

P‐type (100) float zone Si wafers were implanted at room temperature by Ne or He at high dose (5×1016 cm−2) and low energy (50keV or 10keV respectively). Some of them were annealed at low (700°C) and high (1050°C) temperatures to form a close surface buried layer of tiny cavities and to test their thermal stability. Microscopic studies of these sam...

Doppler broadening spectroscopy (DBS) coupled to a slow positron beam has been used to investigate the formation of He-cavities in the presence of high vacancy concentrations in Cz-Si (1 1 1). Si samples were first implanted with MeV Si ions in order to create a damaged Si layer. DBS measurements show the presence of divacancy (S/S=1.052,W/W=0.83)...

SiO2 samples were implanted with 300 keV xenon at various doses: 0.5 to 5 times 1016 Xe/cm2. As-implanted samples show that nm-size precipitates are created for these doses while bubble formation needs doses higher than 1016 Xe/cm . Thermal annealing at 750degC results in the disappearance of nano-precipitates while bubbles/cavities remain stable e...

In this work, we produced thin silicon layers by means of hydrogen implantation. We used 650keV, 1.0MeV, 1.5MeV and 2.0MeV hydrogen for layer thicknesses of about 9, 16, 30 and 48μm according to TRIM simulations. The critical dose was found to be 5×1016H+/cm2 for the first three energies while the highest energy required a higher dose: between 5×10...

We implanted 300keV Xenon in silicon oxide at doses ranging from 1×1016 to 5×1016/cm2. For the first time, we reported the formation and the thermal evolution of bubbles/cavities in SiO2. Characterization by cross-section transmission electron microscopy (XTEM) and Rutherford backscattering spectrometry (RBS) showed that bubbles/cavities remain pre...

Single crystal silicon samples were implanted at room temperature with He ions of different energies (40, 160 and 1550 keV) to the same fluence of 5 × 1016 ions/cm2. Cross-sectional transmission electron microscopy was used to study on the formation of cavities after the subsequent annealing at 800 °C for 1 h. The results show that cavity band can...

The formation of subsurface nm-size cavities in Si from He implantation followed by thermal anneal involves a complex interaction of He with vacancy clusters. We have attempted to promote cavity formation with vacancy-type defects arising from a hydrogen plasma treatment that is interposed between the implantation ( 40 keV and 160 keV He) and annea...

The effects of hydrogen plasma treatment on He-implantation-induced cavities in silicon during subsequent annealing were studied. Silicon samples were first implanted at room temperature with He ions of different energies (40, 160 and 1550 keV) at the same dose of 5 × 1016 cm2, and then were exposed to high density ECR hydrogen plasma for 30 min at...

In this pioneering study, we have extended noble-gas implant-induced cavity generation in Si and other semiconductors to a dielectric, viz., SiO 2 by implanting a variety of inert gas species. It has been seen that helium and neon do not induce bubbles/cavities in SiO2, regardless of implantation parameters and nature of the sample. Krypton and xen...

Float Zone (FZ) silicon samples have been cascade-implanted with helium ions at energies decreasing from 1.9 MeV to 0.8 MeV in steps of 0.1 MeV, with flux maintained between 5 × 1012 and 1 × 1013 He cm-2. The dose was 5×1016 He cm-2 for all the energies except 0.8 MeV where a lower dose of 3×1016 He cm-2 was used. After thermal annealing, the sampl...

We implanted hydrogen in silicon with energies ranging from 500 keV to 2 MeV for implant depths varying from 6.1 to 48.4 μn according to TRIM (transport of ions in matter) 2003. After implantation, a 600 °C thermal annealing was applied to all samples. It is found that for depths lower than 9 μm there is no lift-off of a free-standing silicon layer...

Crystalline silicon samples were first implanted at room temperature with 160 keV He ions at a dose of 5 X 10(16)ions/ cm(2). Some of these samples were then co-implanted with 80 keV Si ions to a dose of 5 x 10(15) ions/cm(2), or were co-treated, with high density hydrogen plasma. Cross-sectional transmission electronic microscopy(XTEM)was used to...

FZ silicon samples were multi-implanted with He ions at energies ranging from 0.8 MeV to 1.9 MeV. The dose was 5$\times$10$^{16}$ He cm$^{-2}$ for all high energies but 0.8 MeV (3$\times$10$^{16}$ He cm$^{-2}$). After implantation, the wafers were submitted to different annealing processes in an Argon atmosphere (A samples: 900 °C and 700 °C for 2...

Damage induced by 1.6 MeV helium implantation of 2×10+16 ions/cm2 in 4H-SiC, at room temperature, was characterized using X-ray Diffraction (XRD) experiments and simulations.

In this paper, we present results on the formation of He-cavities in Si in the presence of vacancies and hydrogen produced by electron cyclotron resonance (ECR) high-density hydrogen plasma treatment. Epitaxial Si (111) samples were first implanted with 1.55 MeV He ions at a dose of 5×10 16cm-2. Subsequent annealing at 800 °C for 30 min creates a b...

Cz p-type Si (100) samples were implanted at room temperature with 160 keV He ions to a dose of 5×1016 cm-2 and were then followed by 80 keV Si ion implantation at different doses ranging from 10 14 to 5×1015 cm-2. Cross-sectional transmission electron microscopy (XTEM) were carried out to study the effects of self-ion implantation induced defects...

Silicon samples were implanted with both 50 keV and 1.55 MeV 3He ions and annealed at different temperatures. The thermal growth of cavities was performed using transmission electron microscopy (TEM) measurements. Results show a significant difference in the formation and growth of cavities. Implantation of 50 keV ions to a total dose of 2.83×1016...

Taking stock of "clean" cavity energies, we conclude that the most important one which controls the cavity shape is the surface energy. Thus, we introduce a cavity shape factor η defining a constant cavity volume. The variations of its corresponding surface energy with η give the cavity equilibrium shape which is taken as reference. Further simulat...

The use of gettering techniques, with precise location of the gettering regions, has become crucial for device manufacturing. Helium-induced cavities have been shown to getter metallic impurities very effectively, but suffer from the drawback of requiring relatively high He doses. In this work, He-implanted Cz wafers of varying resistivity were sub...

Nanocavities were formed in Si by implanting He at different depths: 100 nm (10 keV), 400 nm (50 keV), 1000 nm (160 keV) and 5700 nm (1,55 MeV) according to transport of ions in matter (TRIM) simulation. Different doses were used. After implantation, some samples were subsequently treated by hydrogen plasma. Regarding the depth dependence of cavity...

Different levels of damage were first introduced into CZ p-type Si (100) by the implantation of 80 keV Si ions to different doses ranging from 1014 to 5×1015 cm−2. All the Si implanted samples together with virgin Si were then subjected to 1 MeV 3He ion implantation to the same dose of 5×1016 cm−2. Cross-sectional transmission electron microscopy (...

Results of the comprehensive study of deuterium-implanted hexagonal SiC (4H and 6H) using optical absorption and infrared measurements, elastic recoil detection analysis, thermal desorption and positron annihilation spectroscopies are reported. It is shown that implanted deuterium mainly forms bonds with lattice atoms. The amount of deuterium in...

In this paper, we report the results on the influence of a top oxide layer on the He-cavity formation in silicon samples. Si samples with top oxide layers of different thickness together with the pure silicon (used as reference) were implanted at room temperature with 1 MeV ^3He at a dose of 5×10^{16} He/cm^2. After implantation, the oxide layer wa...

A study of silicon implanted with 1.55 MeV helium 3 and thermally annealed to generate a subsurface cavity region was performed using neutron depth profiling and transmission electron microscopy (TEM). Results show that about 30% of the initial implanted helium is still present in cavities even after a 900 °C-1 h anneal. In addition, TEM measuremen...

Due to recent progress in silicon carbide (SiC) technology, understanding the behaviour of defects in SiC is a crucial challenge for the industrial development of SiC-based devices. High energy helium ion implantation at high fluence in SiC creates a few microns deep damaged layers with nanocavities which are expected to play an important role in g...

In order to provide engineering power devices with a good thermal stabilization of the lifetime with the temperature, we performed a proton implantation following by a helium one. The process resulted in a drastic improvement of the power rectifier parameters particularly a better stabilization versus temperature. While a lifetime control performed...

Cavities were created by MeV He implantation in silicon through a Al foil. After a 800 °C-annealing, unexpected growth mechanism was found: a non-uniform layer of cavities with a distribution where bigger cavities are surrounded by smaller ones. Neither Oswald ripening nor migration-coalescence mechanisms can be applied to describe the growth of th...

Silicon samples were implanted with He ions at 1.6 MeV using doses ranging from 1×1016 cm-2 to 1×1017cm-2 with different fluxes (0.4νA/cm2 - 2.0νA/cm2) and annealed at high (1000°C) and low temperatures (800°C). The implantation induced-defect structure and their distribution in the depth of the sample were studied by cross section electron microsc...

Secondary ion mass spectroscopy measurements (SIMS) and X-ray topography demonstrate the influence of oxygen content in silicon on Ni bulk precipitation and on its gettering behavior at cavities created by high energy He ion implantation. Ni trapping at cavities is efficient in both Czochralski (Cz) and floating zone (FZ) silicon. However, the expe...

4H-SiC samples were implanted at room temperature with 30 keV D + ions at a dose of 5x10 16 D + /cm². Nuclear reaction analysis (NRA) and secondary ion mass spectroscopy (SIMS) measurements were performed to study the deuterium profiles after subsequent annealing at 1000-1250°C for 10min.Also, analytical techniques: RBS/C and thermal desorption spe...

(111) oriented silicon samples were implanted at room temperature with 1.55 MeV 3He ions in the dose range of 5×1015 to 5×1016/cm2. Cross-sectional transmission electron microscopy (XTEM) was used to study the evolution of bubbles and extended defects during subsequent thermal annealing at 800°C and 900°C for 30min. The He desorption from bubbles a...

We implanted silicon at different depth with He-3. We used 1.55 MeV helium implantation and aluminum foils in order to obtain implanted depths ranging from 1.1 to 5.6 mum as simulated by TRIM. All these implantation were done with a dose of 5x10(16) He/cm(2). This dose is higher enough to create cavities for all cases studied. The study showed that...

Silicon samples were gold-diffused at different temperatures, implanted with He ions at 1.6 MeVand then annealed at 1050°C for 2 hours. The implantation induced-defect structure and their distributionin the depth of the sample, studied by conventional and high resolution cross section electron microscopy (HRXTEM) depend on the gold level introduced...

1.6 MeV He+ ions were implanted at room temperature into (0001) 4H-SiC at a dose of 1×1017 cm−2 and then annealed at 1500°C for 30 min. Small bubbles are readily observed in the as-implanted sample but also an amorphous layer. After a 1500°C annealing, recrystallization of the amorphous state occurs and large bubbles or cavities are observed. Howev...

Transmission electron microscopy has been used to study the bubbles and the extended defect formation in crystalline Si implanted with helium at a dose of 1017 cm-2 at 1.6 MeV and annealed at 800°C, as a function of the annealing time of 16.7-1020 min. Below the bubble layer located near the mean projected range, Frank dislocation loops are observe...

Silicon samples were gold-diffused at different temperatures (870–950 °C) and implanted with He ions at 1.6 MeV and fluences ranging from 2 × 1016 up to 1017 cm—2. The implantation induced defects observed by conventional and high resolution cross section electron microscopy were found to be essentially cavities 10 to 100 nm in size which are facet...

A detailed study has been made of helium release from silicon wafers implanted with MeV helium ions at fluences of 5×1016 cm−2 and 1017 cm−2. Thermal desorption spectrometry (TDS), neutron depth profiling (NDP), non-Rutherford elastic backscattering (NREBS) and nuclear reaction analysis (NRA) have been employed to measure the helium content and rel...

We implanted n-type silicon with 1.6 MeV helium at fluences ranging from 1×1016 to 1×1017 He/cm2 while keeping a constant dose rate. These samples were then subjected to 800 °C annealing for 30 min. The results obtained by means of cross-sectional transmission electron microscopy indicate that the density of cavities is fluence dependent with homog...

Pt diffused diodes (p+ n n+ junctions) were manufactured on 75 μm n-type epitaxial Si wafers. Gettering of Pt by 3.1 MeV He-implantation induced defects was performed. The fleunce was 1017 He/cm2. A post thermal annealing at 1050°C for 2 h gave rise to formation of a 0.2 μm cavity layer at the predicted projected range (Rp) as measured by XTEM (cro...

Platinum has been diffused into epitaxial n-type silicon at 600, 650, and 700°C for 30 min following implantation with 3.3 MeV alpha particles. The doses employed were between 1×1011 and 1×1014 He+ cm−2. Thereafter the samples were characterised using DLTS (deep level transient spectroscopy). The samples diffused at 700°C show only the deep level a...

Platinum has been diffused into epitaxial n-type silicon at 600, 650, and 700 °C for 30 min following implantation with 3.3 MeV alpha particles. The doses employed were between 1×1011 and 1×1014 He+ cm−2. Thereafter the samples were characterized using deep level transient spectroscopy (DLTS). The samples diffused at 700 °C show only the deep level...

Platinum has been diffused at 300–800 °C for 30 min into n-type epitaxial silicon samples during 2 MeV electron irradiation using a dose of 1×1017 e− cm−2. Thereafter the samples were characterized by capacitance–voltage measurements and deep level transient spectroscopy. The samples with irradiation temperatures of 500, 600, and 700 °C could be an...

We have evaluated the effect of shallow donors induced by proton irradiation on P+N junctions. We have combined the capacitance–voltage (C–V) technique, which provides the shallow donor profile, and a numerical simulation, based on the solution of Poisson’s equation, to determine the electric field as a function of depth in the N region. This proce...

Platinum has been diffused at 600, 700 and 800°C into n-type epitaxial silicon samples with and without prior 2 MeV electron irradiation at doses of 1×1014–1×1017 cm−2. Without prior electron irradiation, diffusion at 700 and 800°C for 30 min resulted in the presence of a single deep level in the DLTS (Deep Level Transient Spectroscopy) spectrum, w...

Epitaxial silicon samples of n-type have been implanted with 850 keV protons at a dose of 5×1013H+ cm−2. Subsequent in-diffusion of platinum at 700°C for 30 min resulted in the presence of a single deep level, which is attributed to the platinum acceptor level, at 0.23 eV below the conduction band edge. Depth profiling of this level shows that the...

Si(100) samples of n-type have been implanted with 5.6 MeV 28Si3+ at room temperature using a dose of 1×108 cm−2. Thereafter the samples were annealed in nitrogen ambient for 30 min at temperatures from 400°C to 800°C using steps of 50°C. Deep level transient spectroscopy (DLTS) was used for sample analysis. Deep levels, not previously reported in...

Epitaxial silicon samples of n type have been implanted with 850 keV protons at doses of 5.8×1011 to 5×1013 H+ cm−2. Subsequent indiffusion of platinum at 700 °C for 30 min resulted in the presence of a single deep level, which is attributed to the platinum acceptor level, at 0.23 eV below the conduction band edge. Depth profiling of this level sho...

Deep levels created in n-epitaxial silicon by 1.85 MeV proton implantation at a dose of 3.6 × 1013 H+ cm-2 have been investigated by Deep Level Transient Spectroscopy (DLTS). Following irradiation, three hole traps and seven electron traps, two of these for the first time, are observed. They are considered to be (multi-) vacancy- and/or impurity-re...

to 1013particles/cm2 have been investigated by the deep level transient spectroscopy technique and capacitance-voltage profiling. Under low fluence irradiation at least four main electron traps have been observed. With further increase in irradiation fluence, two new levels located at Ec-0.56eV and Ec-0.64eV appear on the high-temperature side of t...

We have irradiated N-type silicon with MeV alpha particles at fluences ranging from 1010 to 5 × 1012 particles/cm2 and at various fluxes. The as-irradiated and post-annealed samples were analyzed by CV measurements carried out as a function of the sample temperature. It clearly appears that as the fluence increases from lower value to higher value...

Defect profiles were determined in proton-implanted low-doped ([P]=1×1014 cm-3) n-type silicon layers by performing positron-electron pair momentum-distribution measurements with a slow-positron beam, conventional positron lifetime, and e+-e- pair momentum-distribution measurements with a 22source and spreading resistance measurements. The dominant...

Bipolar components that consist of p⁺n junctions have been irradiated by MeV protons at fluences ranging from 10¹¹ to 10¹³ particles cm^-2. Capacitance‐voltage measurements have been used to investigate changes in the carrier concentration profiles. Shallow donors that can induce harmful effects in electro...

In order to improve the uniformity of the deposit dose (MeV) ion-irradiated samples, a specific ion beam system has been developed. This system allows us to irradiate samples with different types of scanning (Lissajous, raster scan, circular raster scan) at different sweeping frequencies. This set-up permits to obtain irradiations with a dose varia...

Electrically active defects produced by MeV proton implantation at high doses (1013 H+ cm−2) followed by subsequent annealing (400 °C, 5 min) into n-type silicon have been investigated using capacitance voltage and deep level transient spectroscopy measurements on p+-n-n+ diodes. It was found that the proton implantation followed by the annealing c...

We irradiated N- and P-type silicon with 1.5 MeV protons at fluences of 1012, 1013 and 1014 cm−2. After irradiation, the irradiated samples were studied by the spreading resistance method in order to determine the profiles of the defects before and after different thermal annealings. The measurements were performed as a function of annealing temper...

We irradiated N- and P-type silicon with 1.5 MeV protons at fluences of 1012, 1013 and 1014 cm-2. After irradiation, the irradiated samples were studied by the spreading resistance method in order to determine the profiles of the defects before and after different thermal annealings. The measurements were performed as a function of annealing temper...

We have studied the evolution of the doping profile in power device components after irradiation by protons and alpha particles. Both annealed and unannealed samples were measured by C-V measurements carried out as functions of the sample temperature and of the Fermi level position. For samples irradiated by protons, the deep donors were present be...

Schottky diodes of n-type silicon have been irradiated by 800 keV and 1 MeV protons at doses ranging from 1 × 1012 cm−2 to 1 × 1013 cm−2. Thermally Stimulated Capacitance (TSCAP), capacitance-voltage (CV) and Deep Level Transient Spectroscopy (DLTS) have been applied for sample analysis. By TSCAP measurements a strong compensation effect has been...

The electrical properties of semiconductor components can be greatly modified by proton implantation. Spreading resistance, C-V (capacitance voltage) and DLTS (deep levels transient spectroscopy) measurements have been used to characterize N-type silicon irradiated by MeV proton at fluences up to 10/sup 14/p/sup +/cm/sup -2/. The greatest drawback...