RESEARCH DATA for

Lok Yi Lee, Martin Frentrup, Menno J Kappers, Rachel A Oliver, Colin J Humphreys, and David J Wallis
"Effect of growth temperature and V/III-ratio on the surface morphology of MOVPE-grown cubic zincblende GaN"

Figure 8:
Feature sizes in (a) [110] and (b) [1-10] directions extracted from 2D-FFT of AFM height data of the zb-GaN epilayers grown at different V/III-ratios and a constant growth temperature of 875 °C. (c) Variation of aspect ratio of surface features with V/III ratio. For (a) to (c), there are no data points for the sample grown at a V/III-ratio of 15, as it was not possible to extract feature sizes using the same 2D-FFT method as for other sample in the series. (d) Variation of root mean square surface roughness with V/III-ratio. The labels i, ii and iii indicate the proposed growth regimes. 

(a)
V-to-III	f_[110]	Error
1	µm	µm
15	--	--
23	1.03405	0.03727
38	0.79147	0.08023
76	0.6717	0.02989
152	0.59157	0.02665
300	0.6235	0.06337
600	0.66288	0.04002
1200	0.75427	0.02131


(b)
V-to-III	f_[1-10]	Error
1	µm	µm
15	--	--
23	1.30963	0.08985
38	1.78268	0.1083
76	2.76867	0.20754
152	2.83204	0.48746
300	4.79557	0.45252
600	3.85421	0.42899
1200	2.53846	0.28855


(c)
V-to-III	f_[1-10]/f_[110]	Error
1	µm	µm
15	--	--
23	1.2665	0.13254
38	2.25236	0.36514
76	4.12186	0.49239
152	4.78732	1.03969
300	7.69132	1.50753
600	5.81432	0.99819
1200	3.36546	0.47765


(d)
V-to-III	rms Roughness	Error
1	nm	nm
15	29.68	0.74189
23	14.84	0.47707
38	10.70	0.14491
76	12.00	0.34351
152	12.82	0.34264
300	16.54	1.12898
600	17.00	0.66106
1200	19.76	0.50359