Limits...
InN nanorods prepared with CrN nanoislands by plasma-assisted molecular beam epitaxy.

Liu KW, Chang SJ, Young SJ, Hsueh TH, Hung H, Mai YC, Wang SM, Chen KJ, Wu YL, Chen YZ - Nanoscale Res Lett (2011)

Bottom Line: By inserting CrN nanoislands between AlN nucleation layer and the Si (111) substrate, it was found that we could reduce strain form Si by inserting CrN nanoisland, FWHM of the x-ray rocking curve measured from InN nanorods from 3,299 reduced to 2,115 arcsec.It is due to the larger strain from lattice miss-match of the film-like InN structure; however, the strain from lattice miss-match was obvious reduced owing to CrN nanoisland inserted.The TEM images confirmed the CrN structures and In droplets dissociation from InN, by these results, we can speculate the growth mechanism of baseball-bat-like InN nanorods.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institute of Electro-Optical Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, Republic of China. changsj@mail.ncku.edu.tw.

ABSTRACT
The authors report the influence of CrN nanoisland inserted on growth of baseball-bat InN nanorods by plasma-assisted molecular beam epitaxy under In-rich conditions. By inserting CrN nanoislands between AlN nucleation layer and the Si (111) substrate, it was found that we could reduce strain form Si by inserting CrN nanoisland, FWHM of the x-ray rocking curve measured from InN nanorods from 3,299 reduced to 2,115 arcsec. It is due to the larger strain from lattice miss-match of the film-like InN structure; however, the strain from lattice miss-match was obvious reduced owing to CrN nanoisland inserted. The TEM images confirmed the CrN structures and In droplets dissociation from InN, by these results, we can speculate the growth mechanism of baseball-bat-like InN nanorods.

No MeSH data available.


Related in: MedlinePlus

SEM images for the AlN nucleation layers. Prepared (a) without and (b) with the CrN nanoislands. (c) and (d) show plane view SEM images while (e) and (f) show 60° tilted SEM images for the InN nanorods prepared without and with CrN nanoislands, respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3211861&req=5

Figure 1: SEM images for the AlN nucleation layers. Prepared (a) without and (b) with the CrN nanoislands. (c) and (d) show plane view SEM images while (e) and (f) show 60° tilted SEM images for the InN nanorods prepared without and with CrN nanoislands, respectively.

Mentions: Figure 1a, b shows scanning electron microscope (SEM) images for the AlN nucleation layers prepared without and with the CrN nanoislands, respectively. Without the CrN nanoislands, it can be seen that film-like 2D AlN was grown on substrate. In contrast, dot-like AlN was observed when the CrN nanoislands were inserted. AlN formed a long and continuous grain in Figure 1a; by contrast, the formation of AlN was grown a relatively discontinuous and small as the dot-like grains. The grain density of AlN that without and with CrN nanoisland was about 7.52 × 1013/cm2 and 2.38 × 1014/cm2, respectively. Since CrN nanoisland has been formed on the Si substrate, AlN buffer layer thickness was only 80 nm, as the AlN nucleated on the Si substrate, the Al droplet will be limited to between CrN nanoisland, so the lateral growth of AlN will be inhibited by CrN nanoisland; while the AlN nucleated on the CrN nanoisland, Al droplet of lateral diffusion was more difficult, it also suppressed the lateral growth of AlN, from these reasons, the result as Figure 1a the AlN formed the dot-like structures. Figure 1c, d shows plane view SEM images while Figure 1e, f show 60° tilted SEM images for the InN nanorods prepared without and with CrN nanoislands, respectively. It can be seen that average diameters of InN nanorods prepared without and with CrN nanoislands were both around 100 nm. Compared diameter and uniformity of these two samples, it was also found that InN nanorods prepared with CrN nanoislands were more uniform and more vertically well aligned. Furthermore, it was found that density of the InN nanorods prepared with CrN nanoislands (i.e., 1.26 × 1010/cm2) was significantly more than that prepared without CrN nanoislands (i.e., 6.75 × 108/cm2). Without CrN nanoislands, the roots of the InN nanorods seem to connect with each other, as shown in Figure 1c. This should be attributed to the larger lateral growth rate for the InN nanorods grown on film-like 2D AlN under In-rich condition, under the same growth condition, due to InN nucleated on dot-like AlN nucleation layer was surrounded by low-index planes, {10-10} and {0001}, continuously grew into 1D structure, the InN nanorods lateral growth was suppressed, this reason indicated that InN nanorods can only be grown vertically. Thus, we could achieve more uniform and more vertically well-aligned InN nanorods with a much larger density by inserting the CrN nanoislands.


InN nanorods prepared with CrN nanoislands by plasma-assisted molecular beam epitaxy.

Liu KW, Chang SJ, Young SJ, Hsueh TH, Hung H, Mai YC, Wang SM, Chen KJ, Wu YL, Chen YZ - Nanoscale Res Lett (2011)

SEM images for the AlN nucleation layers. Prepared (a) without and (b) with the CrN nanoislands. (c) and (d) show plane view SEM images while (e) and (f) show 60° tilted SEM images for the InN nanorods prepared without and with CrN nanoislands, respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211861&req=5

Figure 1: SEM images for the AlN nucleation layers. Prepared (a) without and (b) with the CrN nanoislands. (c) and (d) show plane view SEM images while (e) and (f) show 60° tilted SEM images for the InN nanorods prepared without and with CrN nanoislands, respectively.
Mentions: Figure 1a, b shows scanning electron microscope (SEM) images for the AlN nucleation layers prepared without and with the CrN nanoislands, respectively. Without the CrN nanoislands, it can be seen that film-like 2D AlN was grown on substrate. In contrast, dot-like AlN was observed when the CrN nanoislands were inserted. AlN formed a long and continuous grain in Figure 1a; by contrast, the formation of AlN was grown a relatively discontinuous and small as the dot-like grains. The grain density of AlN that without and with CrN nanoisland was about 7.52 × 1013/cm2 and 2.38 × 1014/cm2, respectively. Since CrN nanoisland has been formed on the Si substrate, AlN buffer layer thickness was only 80 nm, as the AlN nucleated on the Si substrate, the Al droplet will be limited to between CrN nanoisland, so the lateral growth of AlN will be inhibited by CrN nanoisland; while the AlN nucleated on the CrN nanoisland, Al droplet of lateral diffusion was more difficult, it also suppressed the lateral growth of AlN, from these reasons, the result as Figure 1a the AlN formed the dot-like structures. Figure 1c, d shows plane view SEM images while Figure 1e, f show 60° tilted SEM images for the InN nanorods prepared without and with CrN nanoislands, respectively. It can be seen that average diameters of InN nanorods prepared without and with CrN nanoislands were both around 100 nm. Compared diameter and uniformity of these two samples, it was also found that InN nanorods prepared with CrN nanoislands were more uniform and more vertically well aligned. Furthermore, it was found that density of the InN nanorods prepared with CrN nanoislands (i.e., 1.26 × 1010/cm2) was significantly more than that prepared without CrN nanoislands (i.e., 6.75 × 108/cm2). Without CrN nanoislands, the roots of the InN nanorods seem to connect with each other, as shown in Figure 1c. This should be attributed to the larger lateral growth rate for the InN nanorods grown on film-like 2D AlN under In-rich condition, under the same growth condition, due to InN nucleated on dot-like AlN nucleation layer was surrounded by low-index planes, {10-10} and {0001}, continuously grew into 1D structure, the InN nanorods lateral growth was suppressed, this reason indicated that InN nanorods can only be grown vertically. Thus, we could achieve more uniform and more vertically well-aligned InN nanorods with a much larger density by inserting the CrN nanoislands.

Bottom Line: By inserting CrN nanoislands between AlN nucleation layer and the Si (111) substrate, it was found that we could reduce strain form Si by inserting CrN nanoisland, FWHM of the x-ray rocking curve measured from InN nanorods from 3,299 reduced to 2,115 arcsec.It is due to the larger strain from lattice miss-match of the film-like InN structure; however, the strain from lattice miss-match was obvious reduced owing to CrN nanoisland inserted.The TEM images confirmed the CrN structures and In droplets dissociation from InN, by these results, we can speculate the growth mechanism of baseball-bat-like InN nanorods.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institute of Electro-Optical Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, Republic of China. changsj@mail.ncku.edu.tw.

ABSTRACT
The authors report the influence of CrN nanoisland inserted on growth of baseball-bat InN nanorods by plasma-assisted molecular beam epitaxy under In-rich conditions. By inserting CrN nanoislands between AlN nucleation layer and the Si (111) substrate, it was found that we could reduce strain form Si by inserting CrN nanoisland, FWHM of the x-ray rocking curve measured from InN nanorods from 3,299 reduced to 2,115 arcsec. It is due to the larger strain from lattice miss-match of the film-like InN structure; however, the strain from lattice miss-match was obvious reduced owing to CrN nanoisland inserted. The TEM images confirmed the CrN structures and In droplets dissociation from InN, by these results, we can speculate the growth mechanism of baseball-bat-like InN nanorods.

No MeSH data available.


Related in: MedlinePlus