Temperature effects on the electrical properties and structure of interfacial and bulk defects in Al/SiNx:H/Si devices

The bonding configuration, hydrogen evolution, and defect content of rapid thermally annealed ͑RTA͒ SiO x :H films of different compositions were studied. Infrared absorption measurements showed that all the hydrogen present in the films is lost at annealing temperatures below 600°C without any change in the oxygen to silicon ratio of the films. The activation energy of the hydrogen release is in the 0.21-0.41 eV range independently of film composition, suggesting that the process occurs via network bond reactions. For annealing temperatures higher than 700°C, a change in the Si-O-Si stretching wave number from the initial unannealed value to the 1070-1080 cm Ϫ1 range was promoted, independently of the initial film composition. Electron spin resonance measurements showed that all the films contain two type of bulk paramagnetic defects: the EЈ center (•SiwO 3 ) and the silicon dangling bond center (•SiwSi 3 ). The RTA process promotes a general decrease of defect concentration for annealing temperatures below 400°C. At higher temperatures, EЈ center disappears, and the •SiwSi 3 center increases its concentration up to the 10 17 -10 18 cm Ϫ3 range. This suggests that the RTA at higher temperatures promotes the formation of a high-quality, almost defect-free, SiO 2 matrix in which highly defective Si nanocrystals are also formed, where the •SiwSi 3 centers are located.

show abstract

“…The density of paramagnetically active centers was quantified by comparison with the signal of a calibrated weak pitch standard. 19 …”

Section: Methodsmentioning

confidence: 99%

Thermally induced modifications on bonding configuration and density of defects of plasma deposited SiOx:H films

Andrés

Prado

Mártil

et al. 2002

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…The density of paramagnetic centers was quantified by comparison with the signal of a calibrated weak pitch standard. 26 Thinner samples ͑80 nm thick͒ were characterized by ellipsometry to obtain the refractive index n of the SiO x H y films. These measurements were performed with a Gaertner L116B ellipsometer operated at ϭ632.8 nm.…”

Section: Methodsmentioning

confidence: 99%

“…24 ͑ii͒ The degree of activation of species is significantly superior in ECR plasmas than in other plasma methods. 25 ͑iii͒ With the ECR plasma method, high quality gate dielectrics can be deposited at low deposition temperatures, 26 achieving the objective of the low thermal budget.…”

Section: Introductionmentioning

confidence: 99%

Bonding configuration and density of defects of SiOxHy thin films deposited by the electron cyclotron resonance plasma method

Andrés

Prado

Mártil

et al. 2003

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

The composition, bonding configuration, hydrogen content, and paramagnetic defects of SiO x H y thin films were studied. Films were deposited by the electron cyclotron resonance plasma method at room temperature using SiH 4 and O 2 as precursor gases. The film composition was measured by heavy ion elastic recoil detection analysis and energy dispersive x-ray spectroscopy. Suboxide films with compositions ranging from SiO 2 to SiH 0.38 were obtained. Infrared spectroscopy showed the presence of different Si-O and Si-H vibration modes. The usual estimation of the oxygen to silicon ratio by the wave number of the Si-O-Si stretching band was not accurate for films far from stoichiometry. These off-stoichiometric films also showed a broader Si-O-Si stretching peak than the stoichiometric ones, indicating a higher bonding disorder. The position of the Si-O-Si bending and rocking modes did not depend on the film composition. On the other hand, the peak position of the Si-H modes were found strongly dependent on the Si environment. By single-wavelength ellipsometry at ϭ632.8 nm the refractive index n was found to range between 1.45 (SiO 2 ) and 2.04 (SiO 0.06 H 0.36 ). Electron spin resonance measurements showed that stoichiometric films presented the well known EЈ center ("SiϵO 3 ) with concentrations in the 10 16 -10 17 cm Ϫ3 range, while for Si-rich films (xӶ1) the Si dangling bond center (Si DB , "SiϵSi 3 ) was the only detectable defect, with concentrations in the 10 18 -10 19 cm Ϫ3 range. In near-stoichiometric films both EЈ and Si DB centers were found.

show abstract

“…Para más detalles del sistema de depósito ver ref. 6. Los gases precursores fueron O 2 de alta pureza para las oxidaciones por plasma, y SiH 4 (1.76 sccm) y N 2 (8.76 sccm) para el depósito de SiN y :H. Esta mezcla de gases produce láminas con un valor de y de 1.55 ( 8 ).…”

Section: Methodsunclassified

Procesos de oxidación de Si mediante plasma de resonancia ciclotrónica de electrones

Andrés¹,

Prado²,

Blázquez³

et al. 2004

Bol. Soc. Esp. Ceram. Vidr.

Self Cite

View full text Add to dashboard Cite

Se han fabricado estructuras MIS sobre Si (100) mediante un proceso en dos pasos: una primera exposición del sustrato de Si a un plasma ECR de oxígeno, que da lugar a la obtención de una capa de SiO x (en adelante PO-SiO x ), seguido de un depósito de nitruro de silicio (SiN 1.55 : H) mediante plasma ECR. La estructura MIS resultante es de la forma Al/SiN 1.55 :H/PO-SiO x /Si. Los dispositivos han sido caracterizados mediante la medida simultánea de las capacidades a alta y baja frecuencia, lo que permite conocer la calidad de la intercara PO-SiO x /Si, calcular los espesores de la capa de PO-SiO x y la velocidad de crecimiento del SiN x :H. Para caracterizar el proceso de oxidación se realizaron varias series de muestras variando en cada una un parámetro del proceso. Estos parámetros fueron: el tiempo de depósito del SiN x :H, el tiempo de oxidación, la temperatura del sustrato y el flujo total de O 2 . Asimismo, se ha estudiado la estructura de enlaces del dieléctrico apilado mediante espectroscopia infrarroja. El espectro del dieléctrico apilado mostró la superposición de dos picos: uno de menor intensidad asociado al PO-SiO x con el máximo en 1056 cm -1 , y otro debido al SiN 1.55 :H con máximo en 860 cm -1 . Estas medidas mostraron que la ley que rige el crecimiento del PO-SiO x es d SiO = 2.7 t ox 0.26 nm donde d SiO es el espesor de la capa de PO-SiO x y t ox es el tiempo de oxidación en min. Por lo que respecta a las características eléctricas, las estructuras presentaron mínimos de la densidad de trampas en la intercara (D it ) cercanos a 10 11 eV -1 cm -2 . Este valor es inferior al que presentaron las estructuras sin oxidar, del tipo SiN 1.55 :H/Si. Además, los dispositivos apilados mostraron un barrido del nivel de Fermi mayor y una histéresis prácticamente despreciable. Palabras clave: Plasma ECR, oxidación por plasma, subóxido de Si, dieléctrico apilado. Si oxidation processes by electron cyclotron resonance plasmasMIS structures have been fabricated on Si (111) by a two-step process: first an exposition of the Si substrates to an ECR oxygen plasma was performed, which yields a layer of SiO x (in the following PO-SiO x ); this process was followed by an ECR plasma silicon nitride deposition (SiN 1.55 :H). The resulting MIS structure is Al/SiN 1.55 :H/PO-SiO x /Si. Devices have been characterized by the simultaneous measurement of the capacitance at high and low frequencies. This measurement lets us know the PO-SiO x /Si interface quality, calculate the thickness of the PO-SiO x layer and the growth rate of SiN 1.55 :H. To characterize the oxidation process some series of samples were prepared. In each series a process parameter was varied. These parameters were: the SiN 1.55 :H deposition time, the ECR plasma oxidation duration, the substrate temperature and the total oxygen flux. The bonding structure of the stacked dielectric has been studied by infrared spectroscopy. The stacked dielectrics spectra showed the superposition of two peaks: a less intense peak associated to the PO-SiO x layer with i...

show abstract

Temperature effects on the electrical properties and structure of interfacial and bulk defects in Al/SiNx:H/Si devices

Cited by 16 publications

References 45 publications

Thermally induced modifications on bonding configuration and density of defects of plasma deposited SiOx:H films

Thermally induced modifications on bonding configuration and density of defects of plasma deposited SiOx:H films

Bonding configuration and density of defects of SiOxHy thin films deposited by the electron cyclotron resonance plasma method

Procesos de oxidación de Si mediante plasma de resonancia ciclotrónica de electrones

Contact Info

Product

Resources

About