Structural and optical properties of thick freestanding AlN films prepared by hydride vapor phase epitaxy

Freitas, Jaime A.; Culbertson, James C.; Mastro, Michael A.; Kumagai, Yoshinao; Koukitu, Akinori

doi:10.1016/j.jcrysgro.2011.12.018

Cited by 19 publications

(15 citation statements)

References 26 publications

(27 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These LVMs perturb the intrinsic crystal vibration, causing the asymmetric line shape of the LO phonon mode. 27 Furthermore, the presence of a high concentration of free-carriers of donor (in this case silicon) or acceptor (mainly carbon) impurities may strongly couple with the A 1 (LO) phonon and can also affect the line shape symmetry. 29 This phonon-plasmon coupling may be one of the reasons why it is quiet difficult to obtain good conductivity in AlN.…”

mentioning

confidence: 99%

Bulk AlN single crystal growth on foreign substrate and preparation of free-standing native seeds

Sumathi

2013

CrystEngComm

View full text Add to dashboard Cite

Physical vapour transport growth of aluminium nitride (AlN) single crystals on silicon carbide (SiC) substrates has been optimised and crack-free, large-area, free-standing (0001) AlN wafers were prepared from the grown template crystals. 28 mm diameter single crystals without any polycrystalline surroundings were obtained. Different off-oriented substrates give rise to different growth modes. Sharp and symmetric line shapes of X-ray diffraction (XRD) rocking curves and high intense Raman phonon mode peaks prove high structural quality and homogeneity of the grown crystals. Full width at half maximum of the rocking curves is 72 arcsec for symmetric 00. demonstrates that AlN templates prepared on SiC as a foreign substrate can be used as native seeds for the growth of further homo-epitaxial layers and crystalline boules.

show abstract

mentioning

confidence: 99%

Bulk AlN single crystal growth on foreign substrate and preparation of free-standing native seeds

Sumathi

2013

CrystEngComm

View full text Add to dashboard Cite

show abstract

“…Inset in Figure 2 demonstrates the position of AlN band 650-665cm -1 . The center of this band after etching has been shifted to 657 cm -1 , which means that mechanical stress is almost absent in the film [9]. …”

Section: Resultsmentioning

confidence: 99%

Separation of stress-free AlN/SiC thin films from Si substrate

Redkov

Осипов

Mukhin

et al. 2016

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

Abstract. We separated AlN/SiC film from Si substrate by chemical etching of the AlN/SiC/Si heterostructure. The film fully repeats the size and geometry of the original sample and separated without destroying. It is demonstrated that a buffer layer of silicon carbide grown by a method of substitution of atoms may have an extensive hollow subsurface structure, which makes it easier to overcome the differences in the coefficients of thermal expansion during the growth of thin films. It is shown that after the separation of the film from the silicon substrate, mechanical stresses therein are almost absent. IntroductionNowadays scientists are actively searching for new ways to obtain high quality semiconductor thin films and heterostructures, in particular, gallium nitride that is used in LEDs and other electronics [1,2] and aluminum nitride. For the growth of such films sapphire and SiC substrates are used mainly [3][4][5], less often silicon or other substrates, but all of these substrates has some disadvantages. Sapphire has very low thermal conductivity and is dielectric, so the additional conducting contacts should be added. SiC is more suitable, because its thermal conductivity is high and close to the conductivity of the copper. In addition, the lattice parameters of SiC and AlN/GaN are much closer to each other [6]. Since SiC substrates are already widely used in practice, it allows one to suggest, that the use of SiC as a substrate for the growth of AlN/GaN heterostructures looks very promising. Nevertheless, a significant drawback of using single-crystal SiC in the manufacturing of devices is the high price of SiC substrates of good quality and desired polytype. One of the promising types of substrates which solves these problems are substrates of nano-SiC/Si, grown by substitution of silicon atoms to carbon atoms [7] directly in the silicon substrate. In fact, the authors of that work for the first time in world practice implemented method of successive substitution of carbon atoms instead of native silicon atoms right inside the substrate without destroying its crystalline structure. The method resembles the "genetic synthesis" of protein structures in biology. The quality of SiC thin film obtained by this method are far superior than quality of films grown on silicon substrates by conventional methods. The method is simple and cheap, and the presence of pores beneath the surface of SiC allows to overcome the mechanical stresses resulting from the lattice mismatch. Thus the study of the method [7] is prospective for the development of thin film technology.

show abstract

“…4, b) до и после отделения. Видно, что после отделения их положение сместилось ближе к позициям 657 и 568 см −1 , соответствующим полностью ненапряженным кристаллам AlN и GaN по данным [28,29].…”

Section: рисunclassified

Отделение эпитаксиальных гетероструктур III-N/SiC от подложки Si и их перенос на подложки других типов

Кукушкин¹,

Осипов²,

Redkov³

2017

Физика И Техника Полупроводников

View full text Add to dashboard Cite

Разработан метод отделения и переноса эпитаксиальных гетероструктур GaN/AlN и AlN, выращенных на кремнии с буферным слоем карбида кремния, на подложки любых типов, основанный на химическом травлении. Гетероструктуры GaN/AlN/SiC толщиной 2.5 мкм и AlN/SiC толщиной 18 мкм отделены и перенесены на стеклянную подложку. Показано, что буферный слой карбида кремния на кремнии, выращенный методом замещения атомов, имеет развитую подповерхностную структуру, которая позволяет легко отделить пленку от подложки и способствует релаксации упругой энергии, вызванной различием в коэффициентах теплового расширения пленки и подложки. Показано, что после отделения плeнки от подложки кремния механические напряжения в плeнке практически полностью релаксировали. DOI: 10.21883/FTP.2017.03.44218.8368

show abstract

Structural and optical properties of thick freestanding AlN films prepared by hydride vapor phase epitaxy

Cited by 19 publications

References 26 publications

Bulk AlN single crystal growth on foreign substrate and preparation of free-standing native seeds

Bulk AlN single crystal growth on foreign substrate and preparation of free-standing native seeds

Separation of stress-free AlN/SiC thin films from Si substrate

Отделение эпитаксиальных гетероструктур III-N/SiC от подложки Si и их перенос на подложки других типов

Contact Info

Product

Resources

About