Selective Epitaxial Growth of GaAs by Liquid Phase Electroepitaxy

Abstract

Selective epitaxial growth of normalGaAs windows (patterns) on SiO2‐normalmasked (100) substrates was achieved by liquid phase electroepitaxy (LPEE). Prior to growth, wells (of the desired depth) were formed in the window areas by selective current‐controlled dissolution. Overgrowth on the SiO2 layer was prevented by arresting epitaxial growth at the SiO2 layer height. Since both selective dissolution and growth rates are proportional to the current density, the depth of the wells and the thickness of the epitaxial layers can be precisely controlled by controlling the current density and process time. Another distinct advantage of the present approach is that, following the formation of the wells, electroepitaxial growth is initiated by simply reversing the polarity of the current passing through the substrate solution interface. Best results regarding the geometry of the wells and uniformity of the epitaxial layers were achieved at relatively low current densities (less than about 15 A/cm2).

Liquid-Phase Epitaxy

“…The current can create a temperature gradient by a combination of Peltier cooling/ heating or resistive heating, and also enhances solute mass transfer by electromigration [142,143] [144]; [145] [146][147][148][149][150][151][152][153][154][155][156]; and [81]; and [157]. The current can create a temperature gradient by a combination of Peltier cooling/ heating or resistive heating, and also enhances solute mass transfer by electromigration [142,143] [144]; [145] [146][147][148][149][150][151][152][153][154][155][156]; and [81]; and [157].…”

Effect of an applied electric current in epitaxial growth of GaAs layer on patterned GaAs substrate

“…Recently, special attention has been paid to the selective epitaxial growth of III-V compound semiconductors to restrict defect propagation into the grown epitaxial layer. A number of recent articles have reported the selective growth of binary and ternary III-V semiconductors by LPE [6][7][8][9][10][11][12][13][14][15][16] and CCLPE [17][18][19][20]. Selective growth by LPE with changing mask layers and mask openings was also investigated [21][22].…”

Aspects of GaAs Selective Area Growth by Molecular Beam Epitaxy with Patterning by SiO2 Masking

“…The GaAs under these windows may be etched to form troughs into which epitaxial GaAs is inlaid or the GaAs may be epitaxially grown on the original substrate surface to form low profile mesa structures. The epitaxy technologies that have been considered are liquid phase epitaxy LPE (1)(2)(3)(4), vapor phase epitaxy VPE (5)(6)(7)(8)(9)(10), and molecular beam epitaxy MBE (11)(12)(13)(14)(15)(16)(17)(18)(19)(20). In MBE, the growth is by impinging thermal energy beams of atoms or molecular species such as As4 or As2 onto the heated substrate.…”