High performance indium phosphide based electronic devices grown by chemical beam epitaxy.

Abstract

The correlation among the design, growth, fabrication, and testing of high performance III-V electronic and electro-optic devices is critical to state of the art electronic device performance. The foundation of this study is chemical beam epitaxy (CBE) which provides unprecedented control of phosphorus based heterostructures, the building blocks of a class of high performance electronic devices. For the first time experimental design work and response surface modeling are applied to epitaxial growth. These techniques represent a significant advance over traditional factorial experimental approaches. By targeting critical parameters, minimizing the number of experiments to be performed, and maximizing the amount of information extracted many bulk material systems can be efficiently built. The relationship between purity of precusors and device performance is directly examined. The first demonstration of CBE growth using trimethylamine alane for the growth of InAlAs and ethyldimethylamine alane for the growth of InAlP are discussed. Detailed understanding of the InGaAs/InP heterointerface is presented along with an algorithm for optimizing the mixed group V heterojunction. The ability to build a digital alloy (InGaAs/InP) is contrasted to growing quaternary InGaAsP in terms of details of growth and resulting device performance. Several classes of devices are examined: the modulation doped field effect transistor (MODFET), the family of resonant tunneling structures, and double heterojunction bipolar transistors. Measured high frequency performance of the MODFET yielded unity power gain cutoff frequency of more than 300 GHz while the DHBT with chirped superlattice showed unity current gain cutoff frequency of 69 GHz and F$\sb{\rm max}$ = 146 GHz. The perspective of this investigation is unique in that it conveys a fundamental appreciation of the cornerstones of the devices being built, relating the design, growth, and fabrication to superior device performance. This vantage point not only provides a view of what is being accomplished but what can be achieved in the future.