High-quality AlN grown with a single substrate temperature below 1200 °C

Abstract

1.5-μm AlN grown by metal-organic chemical vapor deposition (MOCVD), with a single substrate temperature of 1180 °C, exhibits atomically flat surface and the XRD (102) peak width of 427 arcsec. The results are achieved with a pulsed NH3-flow condition, serving as an alternative for the commonly used temperature-varied buffer structure, which is often complicated and time-consuming. Inserting two pulsed-NH3-flow AlN layers in the epitaxial structure not only releases the lattice strain via the formation of three-dimensional nano-islands, but also smoothens the surface with prolonged lateral migration of Al adatoms. This effective growth technique substantially simplifies the manufacture of device-quality AlN.

Ultra-flat AlN grown with a pulsed H2 etching condition

“…The superior crystal quality brought by the annealing effect is further evidenced by XRD measurement (see supplementary information available online at stacks.iop.org/APEX/12/015509/ mmedia), from which the results are summarized in Table I. As discussed in our previous studies, 12) the full widths at half maximum (FWHM) of the symmetric (002) and asymmetric (102) peaks in XRD ω-scans (rocking curves) are correlated to the densities of screw/mixed and edge dislocations, respectively. The dislocation density (N) in the epilayer can be estimated by the equation: [18][19][20][21][22] N = FWHM 2 /(4.35b 2 ), where b is the absolute value of Burgers vector.…”

“…1(b), the two structures were grown with identical conditions. The growth started with a nucleation layer by double-pulsed-flow (DPF) of NH 3 and TMAl, followed by a layer with continuous flows (CF) of the two precursors, then a thin layer with single-pulsed-flow (SPF) of NH 3 , 12) and finally the structure was terminated with an 850 nm CF AlN. All of the layers were grown with a single substrate temperature of 1180 °C.…”

AlN PEALD with TMA and forming gas: study of plasma reaction mechanisms

“…2 High-quality AlN fabrication has been reported with MOCVD. 3,4 However, the growth temperature is generally over 1000 C, which limits the use of low-temperature substrates. Other growth methods such as DC magnetron sputtering 5 and molecular beam epitaxy 6 have been used to deposit AlN.…”

Crystal Transformation of Cubic BN Nanoislands to Rhombohedral BN Sheets on AlN for Deep-UV Light-Emitting Diodes

“…BN and AlN were both attained at the single substrate temperature of 1180 °C and a reactor pressure of 25 mbar. Details of the AlN growth can be found in our previous publications. , Scheme illustrates the growth process of BN. Trimethylaluminum (TMAl), triethylboron (TEB), and ammonia (NH 3 ) diluted in the carrier gas (H 2 ) were employed for Al, B, and N precursors, respectively.…”