Effect of Edge Angles on Growth of Thin Surface Layer of Z-cut NH4H2PO4 Crystal

doi:10.15541/jim20160047

Abstract

Abstract:

The Z-cut NH₄H₂PO₄(ADP) crystal plate samples with different types of edge angle were prepared. During crystal growth experiments, formation and growth characteristics of thin surface layers of different Z-cut plate samples were observed. Meanwhile, the tangential growth rate V and the corresponding kinetics coefficients β of thin surface layers were calculated in the present study. The results show that destruction of the normal angles has significantly influences on “judgment” of the original morphology of Z-cut plate, and further influence formation and growth of thin surface layers. When the thin surface layers meet with each other at normal edge angles, where the intersecting angles form, the thin surface layers generate mainly at intersecting angles and spread out along the edges. This phenomenon suggests that edge angles may be the main origin of thin surface layers. In addition, the average growth kinetics coefficient β_n at normal angle is calculated to be 131.8 μm/s, much higher than 11.6 μm/s of β_a at destroyed angle. These experimental and calculated results suggest that lack of normal angles remarkably decreases the tangential growth rate of thin surface layers.

Key words: ADP crystal, thin surface layer, edge angles, growth kinetics

CLC Number:

CHENG Gao, LI Ming-Wei, YIN Hua-Wei. Effect of Edge Angles on Growth of Thin Surface Layer of Z-cut NH₄H₂PO₄ Crystal[J]. Journal of Inorganic Materials, 2016, 31(11): 1177-1183.

Figures/Tables 9

Fig. 1 Schematic of experimental apparatus for the in-suit observationST: Electronic hot plate; AM: Air lens; S1: Growth solution; S2: Crystal sample; MS: Optical microscope (Nikon 90i); CAM: Camera; CCD: Charge coupled device; CPU: Computer

Fig. 2 Growth characteristics of thin surface layers of Z-cut ADP crystal plate after one edge being cut out(a) Schematic of ADP crystal sample before (ABCE) and after (ABCD) being cut out the edge AE; (b) Emergence of segmented growth of thin surface layers along edge AB(indicated by the arrow) and CD; (c) (101) face starting formation by thin surface layer after edge AE regeneration; (d) Schematic of the segmented growth of thin layer along edge AB

Fig. 3 Growth characteristics of thin surface layers of Z-cut ADP crystal plate without three normal angles(a) Schematic of ADP crystal sample, and the virtual edges HE, HC; (b) Thin surface layers generated from the normal angle ∠CDE and ($\overline{1}$011) face, as indicated by arrows; (e) Formation of prismatic faces formed by thin layer; (f) The final regenerated formation

Fig. 4 Growth characteristics of thin surface layers of Z-cut ADP crystal plate without normal angles(a) Schematic of the crystal sample; (b) (100) face restored by thin surface layers; (c) Schematic of crystal after restoration of prismatic faces; (d-f) Pyramidal faces rapid restoration by thin surface layers forming from each angle

Fig. 5 In-suit observation of formation and growth of thin surface layers originated from angles under optical microscope(a) Extreme thin surface layers formed at edges; (b,c) Thin surface layers spread to edge angle, and the intersecting angle 1 formed; (d-f) Thin surface layers continuously formed at the intersecting angle and spread to edge

Fig. 6 In-suit microscopic observation of the growth of thin surface layer at ∠FAE after partly restored(a) Intersecting ∠2 formed at ∠FAE; (b) Thin surface layers generated rapidly at intersecting ∠2; (c,d) Thin surface layers continuously spread to edge, as shown by white arrows

Fig. 7 Samples used in microscopic experiments and normal ∠1, ∠2, ∠5, and angles with destroy at different degrees (∠3, ∠4 and ∠6)

Table 1 Tangental growth rate of thin surface layer at different angle types

V₁ /(μm·s^-1)	V₂ /(μm·s^-1)	V₃ /(μm·s^-1)	V₄ /(μm·s^-1)	V₅ /(μm·s^-1)	V₆ /(μm·s^-1)	V_3r /(μm·s^-1)
1.386	1.400	0.090	0.080	1.190	0.160	1.090

Table 2 Kinetic coefficients of thin surface layer at different angle types

β₁ /(μm·s^-1)	β₂ /(μm·s^-1)	β₃ /(μm·s^-1)	β₄ /(μm·s^-1)	β₅ /(μm·s^-1)	β₆ /(μm·s^-1)	β_3r /(μm·s^-1)
144.300	150.000	9.375	8.300	120.000	17.000	113.500

References 19

[1]	DE YOREO J J, BURNHAM A K, WHITMAN P K. Developing KH2PO4 and KD2PO4 crystals for the world’s most power laser.International Materials Reviews, 2002, 47(3): 273-285.
[2]	张克从, 张乐潓. 晶体生长科学与技术下册, 2版. 北京: 科学出版社, 1997.
[3]	LI ZHENG-DONG, HUANG XIANG-JIN, XIONG KE-MING.Measurement of electro-optic coefficients of ADP.Journal of Synthetic Crystals, 2001, 30(2):163-166.
[4]	HAN DAI-ZHAO, MA SU-MIN, CAI YU-PING.Symmetry and order parameter of the antiferroelectrics NH4H2PO4.Journal of Synthetic Crystals, 2004, 33(2):254-257.
[5]	SASAKI T, YOKOTANI A.Growth of large KDP crystals for laser fusion experiments.Journal of Crystal Growth, 1990, 99(1): 820-826.
[6]	LI GUO-HUI.Rapid Z-plate seed regeneration of large size KDP crystal from solution.Journal of Crystal Growth, 2008, 310(1): 36-39.
[7]	ZAITSEVA N, CARMAN L.Rapid growth of KDP-type crystals.Progress in Crystal Growth and Characterization of Materials, 2001, 43(1): 1-118.
[8]	ZAITSEVA N, SMOLSKY I, CARMAN L.Growth phenomena in the surface layer and step generation from the crystal edges.Journal of Crystal Growth, 2001, 222(1): 249-262.
[9]	SMOLSKI I, DE YOREO J J, ZAITSEVA N P, et al. Oriented liquid inclusions in KDP crystals.Journal of Crystal Growth, 1996, 169(4): 741-746.
[10]	TENG BING, ZHONG DE-GAO, YU ZHENG-HE, et al.Growth from the edges and inclusion defect of KDP crystal.Journal of Crystal Growth, 2009, 311(3): 716-718.
[11]	ZHANG BING-KAI, YAN MING-SHAN, WANG MAN-FANG.Notes on the growth of single crystal of ammonium dihydrogen phosphate.Journal of Fuzhou University, 1962(2):47-54.
[12]	ZHONG DE-GAO, TENG BING, YU ZHENG-HE, et al.Investigation on the regeneration of Z-cut KDP crystals.Crystal Research and Technology, 2011, 46(9): 911-916.
[13]	ZHONG DE-GAO, TENG BING, DONG SHENG-MING, et al.In-situ study on the effect of Fe~ (3+) on the regeneration on kinetics of Z-cut ADP crystal.Journal of Synthetic Crystals, 2010, 39(S1): 59-63.
[14]	ZHONG DE-GAO, TENG BING, ZHANG SHI-MING, et al.The influence of pH value on the growth mechanism of the thin surface layers formed in the regeneration of Z-cut ADP crystal.Chinese Conference on Crystal Growth, 2009.
[15]	CAO YA-CHAO, LI MING-WEI, YU JIANG-TAO, et al.The microstructure to the phase transition interface of the (100) faces of ADP crystals.Journal of Synthetic Crystals, 2010, 39(6): 1359-1366.
[16]	CHENG MIN, LI MING-WEI, FU DONG, et al.KDP crystal growth in differing pH value.Journal of Chongqing University, 2008, 31(7): 809-814.
[17]	ESTER G R, HALFPENNY P J.Observation of two-dimensional nucleation on the {010} face of potassium hydrogen phthalate (KAP) crystals using ex-situ atomic force microscopy. Journal of Crystal Growth, 1998, 187(1): 111-118.
[18]	TORGESEN J L, JACKSON R W.Growth layers on ammonium dihydrogen phosphate.Science, 1965, 148(3672): 952-4.
[19]	CHERNOV A A. Stability of faceted shapes. Journal of Crystal Growth, 1974, s24-25: 11-31.

Effect of Edge Angles on Growth of Thin Surface Layer of Z-cut NH₄H₂PO₄ Crystal

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