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This research work demonstrates, for the first time, that the material quality of MOVPE III-V QWFET structures on Si can be matched to that of the best MBE III-V QWFET structures on Si. The MOVPE grown In 0.53 Ga 0.47 As QW layer on Si exhibits high Hall mobility of ~8000cm 2 /V-s at 300K, matching that obtained by MBE growth on lattice matched InP (the "gold standard"). IntroductionHigh mobility III-V semiconductors are of interest for transistor channel material applications for high performance and low power logic devices [1-6]. Direct epitaxial growth of such materials on Si substrates is desirable for heterogeneous integration with Si CMOS technology, while avoiding the need for large diameter (≥ 300mm) III-V substrates. However, this poses serious challenges due to the large lattice constant mismatch (e.g. 8% for In 0.53 Ga 0.47 As), coefficient of thermal expansion mismatch, and the generation of polar/non-polar interfaces between III-V and Si. These challenges are being addressed by the use of III-V buffer layer growth, either on blanket [7-10] or on patterned Si wafers [11], which reduces the number of defects reaching active device layers. Most of the research so far has used molecular beam epitaxy (MBE), which offers excellent process control; however, this technique is line-of-sight and non-selective, which poses challenges for process integration and conformal growth on non-planar 3D devices [2]. In contrast, metal organic vapor phase epitaxy (MOVPE) offers the twin advantages of (a) selective area growth and (b) growth on 3-D structures (conformality). To date there have been few studies [8] of MOVPE's feasibility for III-V film growth on Si for logic device applications, and no direct comparisons to MBE have been made. In this work, an InGaAs III-V quantum well field-effect transistor (QWFET) structure [4] (Fig. 1) is used to compare MOVPE and MBE growth processes, demonstrating for the first time that MOVPE III-V material quality can be matched to MBE.

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