Benchmarking and improving III-V Esaki diode performance with a record 2.2 MA/cm² peak current density to enhance TFET drive current

Designing a low-voltage, high-current tunneling transistor

“…Next, In Fig. 4.2(d), we show the current and conductance for an InAs homojunction diode at two different doping levels (NA = 1.8x10 19 ; ND = 3x10 18 and 1x10 19 ) [23]. When the n-side doping is decreased from 1×10 19 /cm 3 to 3×10 18 /cm 3 the absolute conductance I/V swing improves from 570mV to only 180mV/decade falling far short of our goal.…”

“…In the next section we suggest some remedies. [21], (c) a Germanium diode [22], and (d) InAs diodes [23] are plotted. At V=0, the current diverges on a log plot and so the logarithmic slope is meaningless.…”

Performance evaluation of broken gap Esaki tunnel diodes on Si and GaSb substrates

“…The oscillations between the peak and valley current are a common measurement artefact [4,7,8]. Peak voltage (V P ) settles between 0.25 and 0.3 V, as expected for an InAs/GaSb heterojunction in this doping range [5]. Values for J P and PVCR were extracted from over 100 devices.…”

“…Structure: The Esaki diode structure was designed to have a moderately high peak current density (J P ) and peak-to-valley current ratio (PVCR), which maximises the tolerable defect limits as exhibited in prior reports [4]. Doping levels for samples GaSb-TD1 and Si-TD2 were based on designs in Pawlik et al [5] but with a 3 nm i-layer consisting of GaSb. Fig.…”

“…Devices were mesas of varying sizes fabricated via a welldocumented process utilising self-aligned refractory metal contacts [4,5,10,11]. About 200 nm of Mo was blanket deposited on a cleaned sample surface.…”