Abstract

Photonic crystal is a new class of material in which a refractive index is periodically changed.¹ A photonic band gap is formed in the crystal, and the propagation of electromagnetic waves is forbidden for all wave vectors, which gives potential scientific applications such as zero-threshold semiconductor lasers, the absence of spontaneous emission, and single-mode light-emitting diode. In spite of such promising applications, the three-dimensional (3-D) photonic crystal has not been realized yet in optical wavelength region. This is because the shorter the wavelength becomes, the more the process becomes difficult. Thus, the 3-D photonic crystal has been limited to micro- to millimeter-wave regions. In the case of optical wavelength region, a two-dimensional structure has been mainly studied, however, the complete confinement of a light is impossible because a light leaks out to the residual one direction. Therefore, an important issue for the photonic crystal is how to realize the 3-D photonic crystal in optical wavelength region. In this paper, we propose a new method by utilizing a wafer-bonding technique combined with a microfabrication technique.

© 1996 Optical Society of America