An in situ AFM investigation on the morphology of the (100) growth interface of ZTS crystal

Cao, Yachao; Li, Mingwei; Cheng, Min; Song, Jie; Hu, Zhitao

doi:10.1016/j.jcrysgro.2013.07.039

Cited by 11 publications

(10 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Frank pointed out that edge dislocations could serve as nucleation centers for crystal growth . Meanwhile, according to previous studies on the growth of pure ZTS by our group , the outcrops of edge dislocations could act as the centre for the formation of 2D nuclei and promote the growth of crystals. It is found that nucleation occurs preferentially at the outcrops of edge dislocations on the surface whose growth is dominated by 2D nucleation mechanism rather than dislocation mechanism.…”

Section: Resultsmentioning

confidence: 86%

“…However, unlike conventional nucleation‐spread model, 2D nuclei forming at the edge dislocation sites do not spread immediately (in Ref. , the nuclei spread as soon as nucleation). During 6 scanning time intervals in the early stage of growth (the time of acquisition of each image is about 74 s), the spread of nucleus N 1 is not obvious: it spreads only 136 nm in the lateral direction and 155 nm in the longitudinal direction (figures c–h).…”

Section: Resultsmentioning

confidence: 97%

“…Due to the difference in height of the steps S 1 and S 2 (figure l) which intersected perpendicularly, the left step edge of the nucleus N 1 is cut into two parts by dislocation D 2 , one of which was incorporated with the outcrops of dislocation D 2 indicated by the arrow in figure p. Perhaps owing to the “memory function” of nucleation at edge dislocation sites , next nucleation (new nucleus N 2 ) still occurs at dislocation D 1 while no 2D nucleus appears at outcrop of dislocation D 2 . Secondly, it is found that a new stage called “incubation period” is present in the process from nucleation to spread with the addition of EDTA.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

In situ atomic force microscopy studies of growth mechanisms and surface morphology of zinc thiourea sulfate crystals

Song

Cao

et al. 2015

Crystal Research and Technology

Self Cite

View full text Add to dashboard Cite

In situ atomic force microscopy (AFM) has been utilized in studies of the growth mechanism on the (100) face of zinc tris (thiourea) sulphate (ZTS) crystals growing from solution. The growth on the (100) face of pure ZTS crystal is mainly controlled by two dimensional (2D) nucleation mechanisms, under which the hillock is formed through layer‐by‐layer growth. It is easier to form 2D nuclei at edge dislocation and the apex of steps. The growth of 2D nucleus is in accord with nucleation‐spreading mode. The growth rate along the 〈010〉 direction is faster than that along 〈001〉 direction, both of which increase firstly and then decrease with the spread of nucleus. The kinetic coefficients of one nucleus have been roughly estimated to be 3.6 × 10−4 cm/s and 1.8 × 10−4 cm/s in two directions, while the activation energy E was calculated to be 53.7 kJ/mol and 55.4 kJ/mol, respectively. The 2D nuclei can be generated under lower supersaturation with the addition of EDTA. If there are several hillocks growing together, step bunches will form when the steps moving in the same direction meet each other, while the meeting of steps that move in the inverse direction will result in the separation of steps. The ability of nucleation of edge dislocation outcrops are different even they are close to each other on the same surface. When the nucleus was generated at the edge dislocation sites, it cannot spread speedily until finishes an “incubation period”. Moreover, the detour of microsteps was observed due to the existence of pits. If the microcrystals attached on the surface block the step advancement, or leave the surface or are covered by the macrosteps, the pits are formed. If the macrosteps advanced across the pits, the pits will be covered and the liquid inclusions may form. However, if the microcrystal forming in the pit grow up and expose on the surface, the pit will not be covered by macrosteps. The formation of solid inclusions may be caused by the microcrystals being embedded into the single steps which move layer‐by‐layer.

show abstract

Section: Resultsmentioning

confidence: 86%

Section: Resultsmentioning

confidence: 97%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

In situ atomic force microscopy studies of growth mechanisms and surface morphology of zinc thiourea sulfate crystals

Song

Cao

et al. 2015

Crystal Research and Technology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Growth of bulk single crystals of these materials has been a subject of perennial concern to enable them to be useful for device applications. Some examples of semiorganic NLO materials are zin ctris (thiourea) sulphate (ZTS) [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25], bis (thiourea) cadmium chloride (BTCC), zinc thiourea chloride (ZTC) and copper thiourea chloride (CTC). In the present work, the physical, structural, thermal, dielectric and piezo-electric, NLO properties of LMBTZS crystal was studied.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of a NLO crystal - bis (thiourea) zinc sulphate doped with L-malic acid

Sivasankaria¹,

Selvarajan²

2019

SMSJ

View full text Add to dashboard Cite

The nonlinear optical (NLO) material L-malic acid bis(thiourea) zinc sulphate (LMBTZS) was grown by slow evaporation method. The effect of L-malic acid doping on the morphology of the LMBTZS single crystal has been studied. The unit cell parameters were determined by single crystal XRD. The functional groups and force constant of LMBTZS was identified by FTIR analysis. The photoluminescence spectrum of LMBTZS shows the strong emission in ultraviolet region. The thermal behaviours were identified by TG/DTA analyses. Dielectric studies of the grown crystal was carried out. The SHG efficiency was confirmed by powder technique of Kurtz and Perry. LMBTZS is found to be an excellent NLO and piezo-electric material.

show abstract

“…Not only the quality of crystal was improved for the complexation of EDTA with metallic ions, but also the probability of growth unit adsorbing on the surface and entering into the lattice is increased due to decreasing competition with impurities. Compared with the growth of pure ZTS crystal , it is easier for ZTS crystal with EDTA doped to grow under the screw dislocation mechanism if the emergent points of dislocations existed on the surface. On the other hand, the nucleation process also slow down by doping EDTA which is proposed as another reason to explain the observations of the growth of dislocation spiral more easily.…”

Section: Introductionmentioning

confidence: 99%

In situ studies of the spiral growth of zinc thiourea sulphate crystals with ethylene diamine tetraacetic acid doped by atomic force microscopy

Song¹,

Li²,

Cheng³

et al. 2014

Crystal Research and Technology

Self Cite

View full text Add to dashboard Cite

Investigation of crystal growth under screw dislocation mechanisms on the (100) face of zinc tris (thiourea) sulphate (ZTS) crystals doped ethylene diamine tetraacetic acid (EDTA) has been carried out in a fluid cell by in situ atomic force microscopy (AFM). The generation of a dislocation spiral during the step advancing was observed. Through the measurement of the critical length of four sides of a rectangular spiral with a complete growth period, the advancement velocities, step edge free energies and kinetic coefficients of steps have been obtained. The changes in the step velocity with time have been studied. It was found that the relationship between the step velocity and step length is inconsistent with the previous report. The emergent points of dislocations do not disappear even though they are covered by either several elementary steps or macro-steps. It is also shown that the interchange of two spirals whose emergent points of dislocations are adjacent will lead to a distortion of two contiguous steps and affect the growth rates of spirals. The obviously asymmetric growth of spirals of opposite sign in real time was observed. The coexistence and competition of dislocation spirals under different conditions was emphasized considering the activity of dislocation.

show abstract

An in situ AFM investigation on the morphology of the (100) growth interface of ZTS crystal

Cited by 11 publications

References 25 publications

In situ atomic force microscopy studies of growth mechanisms and surface morphology of zinc thiourea sulfate crystals

In situ atomic force microscopy studies of growth mechanisms and surface morphology of zinc thiourea sulfate crystals

Synthesis and Characterization of a NLO crystal - bis (thiourea) zinc sulphate doped with L-malic acid

In situ studies of the spiral growth of zinc thiourea sulphate crystals with ethylene diamine tetraacetic acid doped by atomic force microscopy

Contact Info

Product

Resources

About