Enhanced performance of α-Al2O3 coatings by control of crystal orientation

Orientation control of .ALPHA.-Al2O3 films prepared by laser chemical vapor deposition using a diode laser

“…4(b)) because the (006) plane is inclined at 38°to the (104) plane. 5) Further inclination between the (006) and (012) plane (58°) suppressed isotropic crystal growth of (006) planes, resulted in a pyramidal structure of the (012)-oriented ¡-Al 2 O 3 film (Fig. 4(d)).…”

“…Since the (006) orientation was commonly accompanied by a Journal of the Ceramic Society of Japan 118 [5] 366-369 2010 slight (104) orientation, this structure may be associated with that the (104) plane, which has a 38°angle to (006). 5) At P L = 190 W (T dep = 1100 K), the ¡-Al 2 O 3 film had a pyramid-like structure (Fig. 4(d)).…”

“…The optimum deposition conditions for (006)-, (104)-and (012)-oriented ¡-Al 2 O 3 films were P L = 110, 150 and 190 W, respectively, at P tot = 0.2 kPa and T Al = 443 K. The R dep of highly oriented ¡-Al 2 O 3 films was 50 times greater than that of conventional thermal CVD. Journal of the Ceramic Society of Japan 118 [5] 366-369 2010…”

“…As the hardness and toughness of ¡-Al 2 O 3 film depend on the orientation and structure of coatings, oriented Al 2 O 3 films have attracted increased attention for their potential applications to obtain enhanced mechanical properties. 5), 6) Although the preferred orientation of hard coatings, such as TiN films, has been frequently investigated in chemical vapor deposition (CVD), 7)9) there have been relatively few reports on oriented ¡-Al 2 O 3 films. Ruppi et al reported various oriented films that were deposited using a process by which an oxidizing nucleation step was applied on the Ti(C,O) intermediate layer, results showing that the (006) orientation has a superior cutting performance and enhanced ability to withstand plastic deformation.…”

“…Ruppi et al reported various oriented films that were deposited using a process by which an oxidizing nucleation step was applied on the Ti(C,O) intermediate layer, results showing that the (006) orientation has a superior cutting performance and enhanced ability to withstand plastic deformation. 5) However, the deposition rate was only about 1¯m·h ¹1 , restricting its application for thick film coatings. Furthermore, the complicated deposition process made it difficult for deposition onto various substrates.…”