The electrical breakdown properties of GaAs layers grown by molecular beam epitaxy at low temperature

Abstract

The electrical properties of as-grown low temperature (LT) GaAs grown at 200-300°C have been investigated in the temperature range of I O W 0 0 K. It was found that the resistivity of the LT GaAs layer increased as the growth temperature was increased from 200% to 300°C. Correspondingly, over the same growth temperature range, the breakdown field decreased from 320 kV cm-' !o 80 k\? E -' , yet WE more ? h a one order of magnitude higher than !het of semi-insulating GaAs. The breakdown voltage VeD was found to increase as the measurement temperature was decreased, differing from the behaviour of conventional avalanche breakdown. The transport properties of LT GaAs were characterized by hopping conduction at low electric field and low temperature. The particular properties of the as-grown LT GaAs layers suggest a useful application as an insulator in GaAs field effect transistors (FETS). The predominant ohmic behaviour, resulting from hopping conduction, produces a uniform field in the material, which prevents the breakdown at the gate edge of the FETS or at the surface. The high breakdown strength suggests enhanced performance in power devices.

Transport properties of GaAs layers grown by molecular beam epitaxy at low temperature and the effects of annealing

“…The calibration procedure can be found in Ref. 21. Sample LT4 grown at 375°C, though outside the recognized LT-GaAs growth temperature range, was used to compare the electrical properties.…”

“…Although the resistivity of the LT-GaAs was found to be changed by more than one order of magnitude by this alloying process, and discussed layer, there was no change of the breakdown behavior or the corresponding transport properties. 21 For the purpose of studying the electrical properties of the majority of LT-GaAs layers as used in devices, samples alloyed at 430°C were investigated. The coplanar test structure is shown in Fig.…”

Experimental evaluation of the carrier lifetime in GaAs grown at low temperature

“…[1][2][3][4][5][6][7][8][9]. A key role in the formation of these properties is played by the excess amount of arsenic, incorporated into LT GaAs in the process of low temperature MBE [2][3][4][5][6].…”

Terahertz Optoelectronics with Surface Plasmon Polariton Diode

“…For a given operation frequency, ω , the critical voltage can be obtained from the transparency condition (or ε p ( ω , V c ) = 0), and the carrier balance equation , giving where ω p 0 = ( n 0 e 2 / ε 0 m e ) 1/2 is the plasma frequency of the minority carriers under thermal equilibrium and zero external bias, m e is the electron effective mass in the p -type layer, and q is the electron charge. For N A = 5 × 10 19   cm −3 and f = ω /2 π = 35 THz the critical voltage is V c = 1.57 V, which is more than an order of magnitude lower than the breakdown voltage for the device17. Due to the low effective mass of electrons in the p -doped GaAs ( m e = 0.067  m 0 ) the critical voltage is lower than expected for Si-based ( m e = 0.26  m 0 ) SPPDs, which leads to lower heat dissipation and further justifies the choice of using GaAs.…”