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The BET bromodomain containing protein (BRD4) plays a key role in transcription regulation. Therefore, efforts to generate BRD4 inhibitors with excellent potency and DMPK properties are of clinical value. As a continuing work to improve the stability in in vitro metabolic experiments of liver microsomes of our previously reported 7-methylimidazo[1,5-a]pyrazin-8(7H)-one, our optimization of this poor pharmacokinetics focusing on the phenyl substituent is performed. Fortunately, compound 17 displayed subnanomolar potency (IC50 = 30 nM) against BRD4(1), and its liver microsome stability in human, rat, and mouse are more favorable than previously reported inhibitor 28. Compound 17 exhibited antitumor efficacy with no significant toxicity in xenograft models of pancreatic cancer. In addition, fluorescent probe and nuclei-specific dye were utilized to verify apoptosis-inducing of compound 17 via intranuclear potency in BXPC-3 cell line.

‘precision medicine’ is characterized by the selection of targeted drugs based on genetic characteristics of tumor from patients, and no longer selected basis on the type of cancer tissue. Among them, clinical trials on neurotrophin receptor tyrosine kinase genes (NTRK) have proven that great anti-cancer effects can be achieved in different cancer patients. In this paper, a novel total of twenty compounds in two categories have been designed and synthesized. Results of Kinase activity tests showed that I-9 (TRKA IC50 = 1.3 nM, TRKAG595R IC50 = 6.1 nM), and I-10 (TRKA IC50 = 1.1 nM, TRKAG595R IC50 = 5.3 nM) have significant inhibitory activity, and results of cell viability tests showed that I-9 and I-10 can maintain a great inhibitory effect in the Ba/F3-LMNA-NTRK1 cell line(IC50 = 81.1 nM and 41.7 nM, respectively), and in Ba/F3-LMNA-NTRK1-G595R cell line, I-9 and I-10 have better cell activity (IC50 was 495.3 nM, 336.6 nM, respectively) compared with the positive control drug LOXO-101. These results indicate that I-9 and I-10 are potential TRK inhibitors that can overcome drug resistance for further investigation.

Bromodomain protein 4 (BRD4) is a member of the bromodomain and extra-terminal domain (BET) protein family, which plays a key role in transcriptional regulation. Recent biological and pharmacological studies have enabled linking of the BET bromodomains with diseases, including inflammation and cancer, suggesting that bromodomains are druggable targets. In this study, we made further structural modifications of our previously reported BRD4 inhibitors, to develop new chemical scaffold 3-Hydroxyisoindolin-1-One. Then a series of compounds (10a-q) were synthesized via palladium-catalyzed C H activation and BRD4-inhibitory activities and anti-proliferative effects of these compounds were evaluated. Compound 10e exhibited excellent BRD4-inhibitory activity with IC50 value of 80 nM and anti-proliferation potency with IC50 value of 365 nM in HL-60 (human promyelocytic leukemia) cancer cell lines. We have demonstrated compound 10e modulated the intrinsic apoptotic pathway. In conclusion, these results suggested that compound 10e could be utilized as a BRD4 inhibitor for further leukemia treatment.

BRD4 has emerged as an attractive target for anticancer therapy. However, BRD4 inhibitors treatment leads to BRD4 protein accumulation, together with the reversible nature of inhibitors binding to BRD4, which may limit the efficacy of BRD4 inhibitors. To address these problems, a protein degradation strategy based on the proteolysis targeting chimera (PROTAC) technology has been developed to target BRD4 recently. Herein, we present our design, synthesis and biological evaluation of a new class of PROTAC BRD4 degraders, which were based on a potent dihydroquinazolinone-based BRD4 inhibitor compound 6 and lenalidomide/pomalidomide as ligand for E3 ligase cereblon. Gratifyingly, several compounds showed excellent inhibitory activity against BRD4, and high anti-proliferative potency against human monocyte lymphoma cell line THP-1. Especially, compound 21 (BRD4 BD1, IC50 = 41.8 nM) achieved a submicromolar IC50 value of 0.81 μM in inhibiting the growth of THP-1 cell line, and was 4 times more potent than compound 6. Moreover, the mechanism study established that 21 could effectively induce the degradation of BRD4 protein and suppression of c-Myc. All of these results suggested that 21 was an efficacious BRD4 degrader for further investigation.

The bromodomain and extraterminal (BET) family of proteins play a crucial role in promoting gene expression of critical oncogenes. Novel BET bromodomain inhibitors with excellent potency, drug metabolism and pharmacokinetics (DMPK) properties were in strong need for development. We reported a series of potential BET inhibitors through incorporation of imidazole into pyridine scaffold. Among them, a novel BET inhibitor with 7-methylimidazo[1,5-a]pyrazin-8(7H)-one core, compound 28, was considered to be the most promising for in-depth study. Compound 28 exhibited excellent BRD4-inhibitory activity with IC50 value of 33 nM and anti-proliferation potency with IC50 value of 110 nM in HL-60 (human promyelocytic leukemia) cancer cell lines. Western Blot indicated that compound 28 can effectively trigger apoptosis in BxPc3 cells by modulating the intrinsic apoptotic pathway. In conclusion, these results suggested that compound 28 has merely potential for leukemia treatment.

CuO nanowires were prepared on the copper foil by thermal oxidation in air. The effect of annealing temperature and growth time on the morphology of the nanowires is investigated. It is found that the annealing temperature and the growth time play an important role in the morphology of CuO nanowires such as the density, the length and the diameter. The length and the density of nanowires increase with prolonging growth time; but if the time is too long, CuO crystallite grains form instead of nanowires. Annealing copper foils at lower or higher temperature, the density of nanowires is lower. For comparison, the Cu films on Si substrate deposited by direct current (dc) magnetron sputtering are oxidized, but we do not find large-scale of nanowires. The possible mechanism is also discussed for the growth of CuO nanowires.

Measurements of IR spectra and low energy absorption, using the constant photocurrent method, have been carried out for a-Si:H/a-SiC x :H superlattices fabricated by an r.f. plasma deposition technique. It has been found that there exist high concentrations of Si H bonds and high concentration of Si C bonds at a-Si:H-a-SiC x :H interfaces. The interfacial hydrogen shows a lower thermal stability than that of the hydrogen in the bulk materials. A possible microscopic mechanism of interfacial defects in the a-Si:H/a-SiC x :H superlattices is discussed.

Using a model where a fraction of carbon dangling bonds on the growth surface are saturated by hydrogen, the surface energies of chemical‐vapor‐deposited diamond crystals during the preparation process have been calculated. The results show that the surface energies increase with the increasing substrate temperature, and the surface energy‐temperature curves of the three most energetically favored crystal planes, (100), (110), and (111), intersect at a critical substrate temperature. Then, the changes of predominant facets in the surface morphology from {100} to {111} with the increasing substrate temperature can be interpreted. Furthermore, it is found that the surface energies of diamond are lower than that of graphite in the chemical‐vapor‐deposition process of diamond.

It is proposed in this paper that the minimum substrate temperature for diamond growth from hydrogen-hydrocarbon gas mixtures be determined by the packing arrangements of hydrocarbon fragments at the surface, and the maximum substrate temperature be limited by the diamond growth surface reconstruction, which can be prevented by saturating the surface dangling bonds with atomic hydrogen. Theoretical calculations have been done by a formula proposed by Dryburgh [J. Crystal Growth 130 (1993) 305], and the results show that diamond can be deposited at the substrate temperatures ranging from ≈ 400 to ≈ 1200°C by low pressure chemical vapor deposition. This is consistent with experimental observations.

Highly purified polycrystalline wafers of Zr and Hf were chosen as substrates for diamond deposition by means of the d.c. arc discharge plasma CVD method. Polycrystalline diamond films were formed on both substrates. Scanning electron microscopy and high resolution X-ray diffraction were used to investigate the surface morphology of the diamond films and the composition of the interface layers between the diamond films and substrates. The experiments showed that the transition layer between the diamond films and Zr substrates was ZrC, ZrH and ZrC0.32H1.2. For Hf substrates, in addition to HfC, it is supposed that there were also some hydrides or carbohydrides in the transition layer, because several X-ray reflections appeared which could not be assigned to Hf, HfC or diamond.

We have calculated the surface free energies of the chemical vapor deposited diamond crystals during the preparation process, using the model that a fraction of carbon dangling bonds on the growth surface are saturated by hydrogen. The results show that the surface free energies of the three most energetically favored crystal planes, i. e. (100), and (111), can be used to interpret the changes of predominant facets in the surface morphology from {100} to {111} with increasing substrate temperature. In chemical vapor deposition conditions, it is found that the growth surfaces of diamond are more stable than that of graphite.

By using the technique of elastic recoil detection (ERD), we have measured the hydrogen profiles in a-Si:H/a-Si structure samples annealed at various temperatures with and without electrical bias, and investigated the influence of electrical bias on hydrogen diffusion. The results show that hydrogen diffusion in a-Si is significantly enhanced by the action of electrical bias. The existence of the excess carriers, which are introduced by electrical injection, is considered to be responsible for the enhancement of hydrogen diffusion, and the microprocess of hydrogen transport has been exploited.

Highly photosensitive and narrow band gap a-SiGe: H films have been prepared by the RF glow discharge plasma CVD method. The photosensitivity was 2.01 × 10 5 for the film with an optical band gap of E g = 1.47 eV. H 2 dilution and a relatively high RF power are attributed to the improving of the optoelectrical properties. Thermally induced changes of the a-SiGe:H films have been also investigated.

The creation process of thermally induced defects in B-doped hydrogenated amorphous Six.C1-x samples has been studied by measuring the annealing time dependence of dark d.c. conductivity. The results show that the creation process of thermally induced defects exhibits a stRevched-exponential-like form; the equilibrium values increase with increasing annealing temperature while the relaxation time decreases with increasing annealing temperature. In particular, the stRevched-exponential factor also decreases with increasing annealing temperature, which is contrary to that of the annealing process of frozen-in defects. A model involving two different trapping processes of transportable H in the defect creation and annealing processes is proposed to explain this result.

Boron-doped (B-doped) polycrystalline diamond films (PDFs) were synthesized by thermal filament chemical vapour deposition, and the Hall effect, together with the resistivity of samples with different dosages, was measured by Van der Pauw's method. The Hall mobility and the hole concentration in the samples were also calculated. The experimental results show that B-doped PDFs are p-type semiconductors in which the resistivity has decreased by 11 orders of magnitude compared with the intrinsic samples (from 10 9 Ω cm to 10 −2 Ω cm). The activation energy of the B-doped PDFs was reduced through 0.307 eV (for lightly doped PDFs) to 0.075 eV (for heavily doped PDFs). However, the Hall mobility of the samples was only about 7 cm 2 V −1 s −1 and was almost independent of the impurity concentration. A preliminary discussion of the experimental results is also given in this paper.

The effect of annealing temperatures on the optical-absorption edge of hydrogenated amorphous silicon-carbon alloys (a-SiC:H), prepared by the decomposition of a silane-methane gas mixture highly diluted with hydrogen, has been studied. A comparison of the absorption spectra of a-SiC:H films, obtained by reflectance and transmittance measurements and by the constant-photocurrent method, is presented. The optical band gaps (E g ) decrease and the widths of the band tails (E 0 ) increase with increasing annealing temperature

Studies of current-voltage I–V characteristics of diamond films synthesized by d.c. arc discharge chemical vapour deposition are reported in this paper. Experimental results demonstrated ohmic-type I–V characteristics for as-deposited diamond films with a typical resistivity of the order of 106 ohm; cm. However, the resistivity increased by 6 orders of magnitude, being of the order of 1012 ohm; cm after the diamond films were annealed in a nitrogen atmosphere for 90 min at 600°C, and the I–V characteristics revealed a space-charge-limited current behaviour in the presence of traps at times. When the annealed samples were rehydrogenated in the hydrogen plasma, the resistivity returned to the value of the asdeposited films. An exponential energy distribution of traps and the order of its peak value were also estimated in our work.

The depth profile of the structure of synthetic diamond thin films prepared by the d.c. arc discharge plasma chemical vapour deposition (CVD) method has been investigated by sample-tilting X-ray diffraction. The results show that, at first, a layer of carbide is deposited which saturates the substrate surface. For a single-crystal silicon (c-Si) substrate, the compound is silicon carbide (SiC); for a molybdenum wafer substrate, the compound is molybdenum carbide (Mo2C). A diamond film grows on the carbide layer. The orientation of the crystal grains with depth in the polycrystalline diamond thin films is irregular. The main contaminant in diamond thin films prepared by the d.c. arc discharge plasma CVD method is tungsten carbide (WC).

B-doped a-Si: H thin films and a-SiB: H alloy thin-film materials are prepared by reactive sputtering. The B2H6 concentrations Yg (= [B2H6]/([Ar] + [H2])) vary from 10−6 to 10−2. The ESR (electron-spin resonance) spectra of the samples are studied and found that they are composed of two parts, g1 = 2.0051 and g2 = 2.0096. g1 is the Si30 dangling bond signal, and g2 is the spin signal B-induced in a-Si:H film. With the increases of boron concentration, Yg, g2 varies from 2.0090 to 2.0096, and its peak–peak width, δH2pp, changes from 20.5 to 26.0(10−4T), but g1 and δH1pp do not change obviously. When Yg increases, the density of the two kinds of defects, N1s and N2s, increases too, but N2s changes faster than N1s. In the heavy B-indoped case (Yg ≧ 10), the properties of the samples are different from that discussed above and reveals alloy effects. B-dotierte dunne a-Si: H-Schichten und a-SiB: H-Legierungsschichtmaterialien werden mittels reaktiven Aufspruhens hergestellt. Die B2H6-Konzentration Yg( = [B2H6]/([Ar] + [H2])) variiert von 10−6 bis 10−2. Die ESR (Elektronenspinresonanz)-Spektren der Proben werden untersucht, und es wird gefunden, das sie aus zwei Anteilen zusammengesetzt sind. g1 = 2,0051 und g2 = 2,0096. g1 ist das Si-Danglingbond-Signal und g2 ist das B-induzierte Spinsignal in a-Si: H-Schichten. Mit Anwachsen der Borkonzentration Yg, variiert g2 von 2,0090 nach 2,0096 und die Linienbreite ΔH2pp andert sich von 20,5 auf 26,0 (10−4 T), jedoch andern sich g1 und ΔH1pp offensichtlich nicht. Wenn Yg anwachst, nimmt auch die Dichte der beiden Defektarten, N1s und N2s zu, jedoch andert sich N2s schneller als N1s. Im stark B-dotierten Fall (Yg ≧ 10) sind die Eigenschaften der Proben verschieden von den oben diskutierten und zeigen Legierungseffekte.

Etude des proprietes des defauts metastables induits thermiquement dans les couches de a-Si 1-x Gex:H, par mesure de la variation thermique de la conductivite et de la relation capacite electrique-tension pour differentes vitesses de refroidissement apres recuit. Analyse qualitative des resultats

Cet equilibre est etabli par le mouvement des liaisons H. Ces films, a teneur en H variable, sont prepares en changeant la temperature de depot. On etudie la correlation entre la temperature d'equilibre et la teneur en H

Mesure des profils de profondeur du bore dans les heterojonctions a-SiC:H/a-Si:H dopees par du bore par analyse de la reaction nucleaire (NRA). Analyse des comportements de la diffusion du bore pendant le processus de preparation des heterojonctions. La concentration en atomes de bore dans la couche a-Si:H depend fortement de la temperature du support. La diffusion du bore de la couche a-SiC:H vers la couche a-Si:H durant la croissance resulte en un elargissement remarquable de la zone effectivement dopee. Estimation des coefficients de diffusion du Bore dans les couches a-Si:H pendant leur croissance

Textured cubic boron nitride (c‐BN) films have been deposited on (220) oriented crystallized polycrystalline nickel substrate by a hot filament assisted rf plasma chemical vapor deposition method. X‐ray diffraction shows that the films are (220) preferentially grown, the peak ratio of (220) to the main peak [i.e., the (111) peak] is about 5.2. The scanning electron microscopy images exhibit regular grain shapes. Most of the grains are rectangular, also indicating the (220) growth. The grain size is about 5 μm. The well‐matched Ni lattice with c‐BN, the catalytic effect of Ni, and the appropriate rf bias are considered to be the key factors in the textured growth.

The well‐crystallized cubic boron nitride (c‐BN) films have been prepared on polycrystalline Ni substrates using a hot filament assisted rf plasma chemical vapor deposition method. X‐ray diffraction showed that high quality c‐BN films had been deposited without hexagonal BN (h‐BN) or amorphous BN codeposition. Both (111) and (100) faces were observed in scanning electron microscopy images. These results suggested that Ni had catalyst effects on the nucleation and the growth of c‐BN phase and inhibited the formation of h‐BN.

Fourier‐transformation infrared spectroscopy (FTIR) was used to study C60 thin films which have been annealed for various times. The results show that the intermolecular interactions between C60 molecules in the films affect the vibrational modes. The 1428 cm−1 mode is the most sensitive mode to the interaction. A vibrational mode at about 669 cm−1 appears in the IR spectra of the films and increases with the annealing time; this mode represents the intermolecular interactions between the C60 molecules in the films. The peak position shift and the relative height of 1428 cm−1 mode increase with the increase of the 669 cm−1 mode peak height. The mechanism of the changes of vibrational modes has been discussed.

In order to investigate the growth mechanism of diamond thin films, the in situ optical emission spectra of direct current (dc) arc discharge plasma, including the spatial distributions and different CH4/H2 ratios, have been measured during the growth processes of diamond thin films prepared by the dc arc discharge plasma chemical vapor deposition method. The results show that there are a great number of atomic hydrogens in the arc discharge plasma. This is the key factor for the growth of diamond films with a high rate and high quality. In addition, the effects of the CH4/H2 ratio on the quality of diamond films are discussed in detail in this letter.

Cette methode in situ fournit des densites de spin plus elevees que par mesure de resonance paramagnetique electronique haute temperature conventionnelle. Cette difference est attribuee a un processus de cristallisation qui apparait dans la methode conventionnelle

Etude de la variation de la densite de defauts en equilibre thermique dans les couches a-SiH:H, en fonction de la temperature. Par mesure de resonance de spin electronique (ESR) in situ, on observe directement les defauts en equilibre thermique et on etudie la relaxation des defauts figes

Among the strong carbide forming elements, ten of them have melting points above 1400 degrees Centigrade. The observed transition layers between CVD diamond films and the substrates of Mo, Si, W, Ta, Nb, and Ti have been reported previously. In this paper, further research results on transition layers for the substrate elements of V, Cr, Zr, and Hf are presented. The specimens are prepared in an arc discharge plasma CVD system with the substrate temperature of 900 - 1000 degrees Centigrade and characterized by a high resolution X-ray diffusion diffraction instrument. the experimental results show that the transition layers are polycrystalline VC and V2C, Cr7C3 and HfC for the substrates of V, Cr, and Hf respectively. For the transition layers between CVD diamond films and Zr substrates, the composition of polycrystalline ZrH, ZrC, and their complex compound are verified and the content of hydride is comparable to the content of carbide in this case.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Electron spin resonance (ESR) spectrum have been used to study undoped cubic boron nitride crystals. The results show that the peak-to-peak width of the ESR signal is 27×10-4 T and the g-value is 2.00248, the spin density N s is 2.8×1015 cm-3, it is considered that the ESR signal is originated from the nitrogen dangling bond. Raman spectrum measurements have been also carried out, the peak positions are at 1054 cm-1 and 1306 cm-1.

The nucleation and growth mechanism of polycrystalline diamond films prepared by chemical vapor deposition (CVD) have received increasing research interest. To verify the existence of the transition layers between CVD diamond films and substrates, and to investigate their composition, structure and properties are very meaningful research topics for understanding the mechanism of diamond film growth and developing the applications of CVD diamond films. In this work, the transition layers of carbides for the substrates of molybdenum (Mo), silicon (Si), tungsten (W), tantalum (Ta), and niobium (Nb) and titanium (Ti) have been systematically studied by x-ray diffraction characterization. The experiment results have provided evidence of the existence of transition layers and have revealed that the transition layers are polycrystalline Mo2C, SiC, WC and W2C, TaC and Ta2C, NbC and Nb2C, as well as TiC for the substrates of Mo, Si, W, Ta, Nb and Ti, respectively.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In order to investigate the nucleation and growth mechanisms of diamond thin film, the in situ optical emission spectra (OES) of direct-current (DC) arc plasma chemical vapor deposition (CVD) have been measured during the growth processes of diamond thin films under the case of various CH4/H2 and C2H2/H2 ratios. We compared the results of OES with that of Raman spectra. The results show that there are a great numbers of atomic H in the arc discharge plasma, this is the key factor of the growth of diamond thin films with a high rate and high quality, furthermore, the carbon sources and the H2 dilution ratios have strong effects on the quality of the films. When the ratios of CH4/(CH4+H2) and C2H2/(C2H2+H2) increase, the non-diamond carbon phase in the films increase due to the increasing of C2 radical and the decreasing of atomic H, moreover, when the carbon source is C2H2, and when C2H2/H2=2%, the IG/ID derived from Raman spectra is 33%, but when CH4 is served as carbon source and CH4/H2=2%, the IG/ID=10%, obviously as a carbon source, CH4 is better than C2H2.

Hydrogenated amorphous carbon films were prepared by rf glow discharge decomposition of pure methane at various deposition conditions. The structure and properties of the films have been investigated in respect to the growth rate, conductivity, hardness and bonding structure as a function of substrate temperature, rf power and total gas pressure. The bonding structure has been determined by infrared absorption and electron energy loss spectrum measurements. It is found that a diamond-like film with a hardness of 2200 kg/mm 2 can be deposited under the optimum deposition condition. The properties of the films used as a protective coating has also been investigated.

The influence of argon ion and CO 2 laser irradiation on the structure properties of diamond-like carbon films is reported. The structure ratio of sp 2 /sp 3 -CH bond in the films increases as the argon ion irradiates while it decreases as the CO 2 laser irradiates , which show that the argon ion irradiation is main for breaking the C-H bond while the laser irradiation is a kind of process of thermal annealing.

Afin d'etudier les proprietes des atomes d'hydrogene dans Ge: H amorphe, on mesure la concentration en hydrogene et les profils d'hydrogene dans des films de Ge: H, a l'aide d'une methode d'analyse de reaction de resonance nucleaire. On mesure egalement la stabilite des atomes d'hydrogene afin d'analyser l'influence de l'hydrogene sur les proprietes des films

The vibrational excitations in a-Si1−xNx: H films are calculated in terms of a simplified amorphous cluster. The main vibrational modes as well as correlative frequencies and intensities are obtained. By means of a random substitution of nitrogen atoms for silicon atoms the phonon density of states at different x values are deduced. It can be found that the results are in accord with the experimental Raman spectra. Die Schwingungsanregungen in a-Si1−xNx: H-Schichten werden mit einem vereinfachten amorphen Cluster berechnet. Sowohl die mittleren Schwingungsmoden als auch die Korrelationsfrequenzen und -intensitaten werden erhalten. Mittels statistischer Substitution von Stickstoffatomen fur Siliziumatome wird die Phononenzustandsdichte bei verschiedenen x-Werten abgeleitet. Es wird gefunden, das die Ergebnisse in Ubereinstimmung mit experimentellen Ramanspektren sind.

We have performed the molecular orbital calculations on a 18-atom cluster which is used to simulation the dangling bond having a hydrogen as its neighbor. The isotropic electron spin resonance hyperfine splitting (A value) is calculated. The effects of local atomic relaxations on the A value and orbital energy are also discussed.

Thermally induced metastable defects in P- and B-doped hydrogenated amorphous silicon carbon films have been investigated with electron spin resonance (ESR) technique. By using a special heating resonator, we were able to anneal the samples in situ during ESR measurements and directly observe the temperature dependence of the spin density in the samples. The effects of thermal quenching and annealing on the spin density have been also investigated. A simple discussion for the results of our experiments is presented as well.

The characteristics of light soaking and equilibrium electron spin resonance (ESR) in p‐hydrogenated amorphous silicon‐carbon/i‐hydrogenated amorphous silicon heterojunction are investigated. The influence of the carbon content in the p layer on ESR is also studied in this letter. We find that the light‐induced silicon dangling bond defects mainly originate from the i layer and the increased spin density can be decayed by annealing at a low temperature (160 °C). Possible microscopic mechanisms of the light‐induced defects observed in the p/i heterojunction are discussed as well.

We have achieved the high quality hydrogenated amorphous silicon-germanium (a-SiGe:H) films with high photo-conductivity (σph=10-4S/cm, under AM-1) and high photo-sensitivity (σph/σd=104) by reactive sputtering. In this paper, we present also the electron spin resonance(ESR)-studies of defects are attributed to Si- and Ge-like dangling bonds of a-SiGe:H films.© (1989) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Hydrogen concentration, boron concentration, and their depth profiles in boron‐doped hydrogenated amorphous silicon‐carbon films have been measured by nuclear reaction analysis. We find that the concentrations of hydrogen and boron in the films depend on the doping gas ratio of B2H6 to SiH4+CH4. With the increase of the boron doping gas ratio from 10−4 to 10−2, the hydrogen concentration decreases from 38.7 to 6.2 at. % and the boron concentration increases from 0.0094 to 1.2 wt. %. A simple discussion for the results obtained is also presented.