Compound Semiconductors for Low-Power p-Channel Field-Effect Transistors

Abstract

Research in n-channel field-effect transistors based upon III-V compound semiconductors has been very productive over the last 30 years, with successful applications in a variety of high-speed analog circuits. For digital applications, complementary circuits are desirable to minimize static power consumption. Hence, p-channel transistors are also needed. Unfortunately, hole mobilities are generally much lower than electron mobilities for III-V compounds. This article reviews the recent work to enhance hole mobilities in antimonide-based quantum wells. Epitaxial heterostructures have been grown with the channel material in 1-2% compressive strain. The strain modifies the valence band structure, resulting in hole mobilities as high as 1500 cm 2 /Vs. The next steps toward an ultra-low-power complementary metal oxide semiconductor technology will include development of a compatible insulator technology and integration of n-and p-channel transistors.

In situ grown Ge in an arsenic-free environment for GaAs/Ge/GaAs heterostructures on off-oriented (100) GaAs substrates using molecular beam epitaxy

“…[2][3][4][5]; however, the demonstration of an equally high-performance p-channel QW within the same material system with similar performance remains elusive to date due to low hole mobility in III-V materials without which energy efficient complementary logic circuits will not be realized. Although, strained III-Sb materials, namely InSb, 6 InGaSb, [7][8][9][10] and GaSb 11,12 materials are potential p-channel candidates, Ge has much higher bulk hole mobility ($1900 cm 2 V À1 s À1 ) even without strain compared to III-Sb materials (800-850 cm 2 V À1 s À1 ). The theoretical investigations of hole transport in 1.5-2% biaxially strained III-V semiconductors show an increase in the hole mobilities up to a factor of 2 over unstrained value [3][4][5][6][7][8][9][10][11][12][13][14][15] ; however, the hole mobility in 2% bi-axially strained bulk Ge can be increased up to 4000 cm 2 V À1 s À1 , 16 which is significantly higher than any III-V materials.…”

“…Although, strained III-Sb materials, namely InSb, 6 InGaSb, [7][8][9][10] and GaSb 11,12 materials are potential p-channel candidates, Ge has much higher bulk hole mobility ($1900 cm 2 V À1 s À1 ) even without strain compared to III-Sb materials (800-850 cm 2 V À1 s À1 ). The theoretical investigations of hole transport in 1.5-2% biaxially strained III-V semiconductors show an increase in the hole mobilities up to a factor of 2 over unstrained value [3][4][5][6][7][8][9][10][11][12][13][14][15] ; however, the hole mobility in 2% bi-axially strained bulk Ge can be increased up to 4000 cm 2 V À1 s À1 , 16 which is significantly higher than any III-V materials. Considering several material choices and strain engineering in the channel, Ge epitaxial film grown on a large bandgap GaAs material is of immense interest due to lattice match (mismatch $0.07%) which ensures larger critical thickness, lower dislocation density, and strain-free Ge epitaxial film.…”

Benchmarking the performance of ultrathin body InAs-on-insulator transistors as a function of body thickness

“…High-mobility semiconductors have been actively explored in the recent years for use as the channel material of field-effect transistors (FETs) to enable low-power and highspeed electronics. [1][2][3][4][5][6] In this regard, the use of ultrathin layers of III-V semiconductors on conventional Si substrates has been recently explored, taking advantage of the excellent electrical properties of III-Vs along with the well-established processing technology of Si. 3,5 Two distinct approaches have been proposed; one utilizing the direct epitaxial growth of complex multilayers on Si 3,7 and the other involving the layer transfer of ultrathin films from a III-V source wafer onto a Si/SiO 2 handling substrate.…”

Surface Morphology of AlSb on GaAs Grown by Molecular Beam Epitaxy and Real-time Growth Monitoring by in situ Ellipsometry

“…Other good point of Sbbased material system is that the mobility is larger than conventional GaAs, InP and Si. Recently, researchers of Naval Research Laboratory in USA succeeded in the fabrication of Sb-based n-and p-channel heterostructure field effect transistor for high-speed and low-power application [8,9].…”