(Invited) Epitaxial III-Nitride Film Growth in a Single Wafer Rotating Disk MOCVD Reactor

Abstract

We are reporting on the epitaxial growth of Al/Ga/N films on 200 mm Si substrates carried out in Veeco's Propel rotating disk, single wafer, vertical MOCVD reactor. The Turbodisc reactor is designed for uniform alkyl and hydride flow distribution, and temperature profile, resulting in uniform and concentrically symmetric epilayer thickness and chemical composition. Results are presented on film stress and wafer curvature control facilitated by adjusting the thickness and growth conditions of individual layers in AlN/GaN superlattices. The growth of highly resistive, intrinsically carbon-doped GaN layers is studied, and the influence of growth conditions, growth temperature, pressure, and V/III ratio, on carbon incorporation rate, crystal quality, and surface morphology will be discussed in this paper. Carbon incorporation is enhanced at lower growth temperature, lower pressure, and lower V/III ratios; we have obtained concentrations as high as 3E19/cm 3 at a growth pressure of 35 Torr and growth temperature of 960 °C.

Study of GaN doping with carbon from propane in a wide range of MOVPE conditions

“…3, the dependence of carbon concentration in GaN on ammonia flow for all studied growth rates roughly follows the law C GaN $(X NH3 ) À 2 . The magnitude of the effect is similar to what was reported in [9,10] and much higher than in [11] for the dependence of background carbon concentration in GaN epilayers on ammonia flow.…”

“…It is well known that reduction of ammonia flow leads to increase of carbon background concentration in nominally undoped GaN epilayers [9][10][11]. We have observed the same effect for the case of intentional doping (see Fig.…”

“…means change of other reactor conditions like TMGa and ammonia flows or reactor pressure. Previous extensive investigations [2,[9][10][11] have shown that these parameters influence carbon background incorporation in nominally undoped GaN epilayers. A study of similar dependencies in the case of intentional doping of GaN from carbon precursors is important.…”

High Breakdown Voltage and Low Buffer Trapping in Superlattice GaN-on-Silicon Heterostructures for High Voltage Applications

“…For asymmetrical plane GaN (102), the Full width at half maximum (FWHM) was 991 arcsec for the SL and 1216 arcsec for the reference wafer. The FWHM of GaN (102) is dependent on all types of threading dislocations (TDs), i.e., edge (TEDs), screw (TSDs) and mixed type and thus a measure for the overall structural quality of GaN [ 18 ]. The lower value found on the SL wafer confirms the better crystal quality of this structure.…”

Gallium Nitride Doping with Carbon: A Thermodynamic Analysis

“…The first one (GT T ¼ 950 C, reactor pressure P ¼ 50 mbar) provides high carbon incorporation, %10 19 cm À3 , into GaN, whereas another condition (GT T ¼ 1100 C, reactor pressure P ¼ 200 mbar) gives a low, %10 16 cm À3 , carbon concentration in the material. [28] The former conditions are typical for growth of high-resistance GaN:C buffer layers in laterally aligned HEMTs, [29] whereas the latter ones are important for growing structures for vertical devices with minimal carbon incorporation in thick drift layers. [30] The application of the thermodynamic model described earlier to those growth conditions gives the results shown in Figure 3.…”