On-state and off-state breakdown in GaInAs/InP composite-channel HEMT's with variable GaInAs channel thickness

Breakdown in millimeter-wave power InP HEMTs: a comparison with GaAs PHEMT's

“…Composite channels [34], [35], compositionally graded channels [36], and quantized channels [35] have all been investigated toward this goal, although longlasting benefit has not been obtained beyond 60 GHz. Cap recess engineering should also be an effective approach for improving .…”

Scaling Rules for Multi-Finger Structures of 0.1-μm Metamorphic High-Electron-Mobility Transistors

“…The enhancement of power characteristics can be achieved by improving the current level or breakdown voltage of the HEMTs. A variety of methods have been used to increase the power performance of HEMTs these include the GaN/AlGaN material system [5,6], the gate-fieldplate technique [7,8], and the adoption of composite channel systems [9,10]. Most of these methods have focused on the enhancement of transistor power by increasing the breakdown voltage.…”

Determining dominant breakdown mechanisms in InP HEMTs

“…On the other hand, as is decreased, the relative importance of II grows. This illuminates work on lightly doped devices which showed a dependence on channel composition and quantization, as well as signatures of II in breakdown [3], [6], [12].…”

“…The cause of this behavior is a subject of debate-it has been variously claimed that impact ionization (II), thermionic field emission (TFE), tunneling, or some combination thereof are responsible for off-state breakdown [2]- [6]. Furthermore, different devices may suffer from different breakdown mechanisms, depending on the details of the design (insulator thickness, recess, channel composition, and so forth).…”