High voltage devices with multi-electrode control

Abstract

In the depicted example, a high voltage transistor (HVT) structure (140) adapts a low voltage transistor (LVT) (110) to a high voltage environment. The HVT structure (140) includes a drain node (152), a source node (154), a control gate (156), and field electrodes (162, 164). The drain node (152) and source node (154) define a conductive channel (163, 165) in which the transferred charge is regulated by the control gate (156). When isolated from the control gate (156), the field electrodes (162, 164) are configured to spread the migrating charge in response to the field voltage. The field electrodes (162, 164) are structured and wired to prevent charge sharing with any of the drain node (152), source node (154) or control gate (156). Advantageously, the isolated field electrodes (162, 164) minimize the capacitance of the control gate (156) to the drain and source nodes (152, 154) so ​​that the HVT (140) can operate in a high voltage environment with relatively low Small power loss and more robust performance for switching.

Description

Background technique [0001] Silicon-based transistors are well suited for low-voltage applications. But in high voltage applications (eg, supply voltages greater than 100V), the breakdown voltage of silicon-based transistors increases, causing a disproportionate increase in the channel resistance of silicon-based transistors. As a result, a large trade-off exists in the BV*Ron figure of merit. Increasing the breakdown voltage of silicon-based transistors also significantly increases the transistor's device capacitance, which typically slows down the transistor's switching efficiency. [0002] To address these issues, high-voltage devices are used in cascode configurations with silicon-based transistors. The high voltage device may be a high electron mobility transistor (HEMT), such as a gallium nitride (GaN) HEMT. Generally, a GaN HEMT includes a two-dimensional electron gas (2DEG) channel, which provides a high breakdown voltage and enables ultra-high power density operati...

AI Technical Summary

Problems solved by technology

[0003] Ringing suppressors suppress ringing, but this increases power loss and reduces switching efficiency in cascaded configurations

Images