Integrated Optics - Applied Optics Fundamentals and Device Applications - page 257

Lens contour

V-cut LiNbO 3

Ti region

TIPE region

(a)

(b)

FIGURE 5.23
Planar waveguide lens in LiNbO formed by titanium-indiffused proton-exchange technique
(a) top side, (b) side view.

devices are expected to greatly facilitate the development and implementa-
tion of integrated and fiber-optic signal processing and computing.

5.10 SemiconductorWaveguideFabricationTechniques
A wide variety of methods are used to fabricate optical waveguides and com-
ponents. These include thin-film deposition, epitaxial growth, filled channel
techniques, ion diffusion, and ion implantation. Several of these techniques
have been discussed in other sections. This section covers the techniques
most conducive to integration and production of optical circuits—namely,
MOCVD, MBE, and ion implantation—along with a discussion on foundry
facility utilization.

5.10.1 Ion Implantation

Ion implantation is a particularly valuable technique that offers a number
of distinct advantages in comparison to the other fabrication methods [80].
In ion implantation a beam of atoms is ionized, accelerated to kinetic ener-
gies up to several million electron volts, and directed at a suitable material
target. The resulting damage in the material and the introduction of foreign
atoms can produce electronic, chemical and optical changes. The primary