Heteroepitaxy, an Amazing Contribution of Crystal Growth to the World of Optics and Electronics

Abstract

Advances in Electronics and Optics are often preceded by discoveries in Crystal Growth theory and practice. This article represents in retrospect some of the most significant contributions of heteroepitaxy in these and some other areas-the strong impact of the three modes of heteroepitaxy on microelectronics and quantum optics, the big "push" of PENDEO epitaxy in development of Light Emitting Diodes, etc. A large part of the text is dedicated to heteroepitaxy of nonlinear optical materials grown on orientation-patterned templates and used in the development of new quasi-phase-matching frequency conversion laser sources. By achieving new frequency ranges such sources will result in a wide variety of applications in areas such as defense, security, industry, medicine, and science. Interesting facts from the scientific life of major contributors in the field are mixed in the text with fine details from growth experiments, chemical equations, results from material characterizations and some optical and crystallographic considerations-all these presented in a popular way but without neglecting their scientific importance and depth. The truth is that often heteroepitaxy is not just the better but the only available option. The truth is that delays in device development are usually due to gaps in materials research. In all this, miscommunication between different scientific communities always costs vain efforts, uncertainty, and years of going in a wrong scientific direction. With this article we aim to stimulate a constructive dialog that could lead to solutions of important interdisciplinary scientific and technical issues.

Thick Hydride Vapor Phase Heteroepitaxy: A Novel Approach to Growth of Nonlinear Optical Materials

“…For example, when one is trying to grow a film with a smaller lattice constant on a substrate with a larger lattice constant then the lattice mismatch is negative and the film is growing under tensile stress, in difference to the case when the lattice mismatch is positive and the growing layer is compressively strained. [20] (reproduced from [20] with some modifications with the permission of Crystals).…”

“…In all of these three cases the slowest step is Figure 2. The three growth modes of heteroepitaxy: (a) Layer-by-layer (Frank-Van der Merwe) growth; (b) island (Volmer-Weber) growth; (c) layer-plus-island (Stranski-Krastanov) growth [20] (reproduced from [20] with some modifications with the permission of Crystals).…”

“…Thus combining these two materials by growing heteroepitaxially GaP on the readily available high quality OP-GaAs templates seemed logical. These attempts turned out to be successful [18][19][20] in spite of the relatively large negative lattice mismatch (−3.6%) between GaP and GaAs.…”

“…Achieving a better understanding of the complex growth and strain relief mechanisms [18,20] during GaP/GaAs heteroepitaxy allowed us to predict other potentially successful heteroepitaxial cases. Some of these cases, due to their smaller lattice mismatches, are even more favorable than GaP/GaAs.…”

“…Attempts to replace the OP templates with the much simpler half-patterned (HP) templates [20] are also described. Some efforts for growth or preparation of QPM structures, including hybrid organic-inorganic QPM structures, without using any patterned templates are also presented [29].…”