The influence of electron energy quantization in a space-charge region on the accumulation capacitance of InAs metal-oxide-semiconductor capacitors

Abstract

The influence of electron energy quantization in a space-charge region on the accumulation capacitance of the InAs-based metal-oxide-semiconductor capacitors (MOSCAPs) has been investigated by modeling and comparison with the experimental data from Au/anodic layer(4-20 nm)/n-InAs(111)A MOSCAPs. The accumulation capacitance for MOSCAPs has been calculated by the solution of Poisson equation with different assumptions and the self-consistent solution of Schrödinger and Poisson equations with quantization taken into account. It was shown that the quantization during the MOSCAPs accumulation capacitance calculations should be taken into consideration for the correct interface states density determination by Terman method and the evaluation of gate dielectric thickness from capacitance-voltage measurements.

A pertinent approximation of the electrostatic potential in a quantized electron accumulation layer induced at a nonideal surface of a narrow‐gap semiconductor

“…[32][33][34] This tendency still persists. 13,35 A useful approach simplifying the calculations in solid-state structures is the fitting of the potential well shape with an analytical function for which an analytical solution of the Schrödinger equation may be found. Up to date, there have been only few such functions proposed for semiconductors.…”

“…[1][2][3][4][5][6][7][8][9][10] In particular, considerable recent attention has been focused on the layers formed in narrow-gap A 3 B 5 semiconductors. [11][12][13] This is partly in connection with the use of these materials in high-performance optoelectronic devices, [14][15][16][17] in the context of scanning tunneling microscopy studies, 18 etc. Under the influence of different band-bending sources (alkali metals, silver and antimony adatoms, cleavage defects, etc) 1,19 or under the external electric field due to, for instance, a bias voltage V G applied to the metal-insulator-semiconductor (MIS) structure, the motion of electrons (at V G > 0) near a semiconductor surface becomes restricted by walls of the induced potential well.…”

“…Electron accumulation layers induced at semiconductor surfaces are of longstanding great scientific interest . In particular, considerable recent attention has been focused on the layers formed in narrow‐gap A 3 B 5 semiconductors . This is partly in connection with the use of these materials in high‐performance optoelectronic devices, in the context of scanning tunneling microscopy studies, etc.…”

“…Attempts to solve the emerging problems were made in a due course by performing fully self‐consistent computations of indicated characteristics including free‐carrier density profiles and wavefunctions . This tendency still persists …”

Исследование плотности интерфейсных состояний на границах раздела диэлектрик / In-=SUB=-0.52-=/SUB=-Al-=SUB=-0.48-=/SUB=-As

“…Измерения проводились в режиме параллельной цепи с использованием синусоидального тестового сигнала с амплитудой 5 mV в темноте при температуре 310 K. Частота переменного сигнала во всех измерениях составляла 1 kHz, так как при повышении частоты наблюдалось существенное уменьшение емкости в режиме обогащения, что связано с влиянием последовательного сопротивления слоя i-InAlAs и осложняет интерпретацию ВФХ. Методика расчета теоретических ВФХ в предположении отсутствия интерфейсных состояний в полной мере описана в работах [13,14]. При расчетах значение работы выхода металла полагалось равным 4.9 eV.…”