Transistor or semiconductor device and method of fabricating the same

Abstract

Provided are a transistor of a semiconductor device and method of fabricating the same. The transistor includes: an epitaxy substrate disposed on a semi-insulating substrate and having a buffer layer, a first Si planar doping layer, a first conductive layer, a second Si planar doping layer, and a second conductive layer, which are sequentially stacked, the second Si planar doping layer having a doping concentration different from that of the first Si planar doping layer; a source electrode and a drain electrode diffusing into the first Si planar doping layer to a predetermined depth and disposed on both sides of the second conductive layer to form an ohmic contact; and a gate electrode disposed on the second conductive layer between the source and drain electrodes and being in contact with the second conductive layer. In this structure, both isolation and switching speed of the transistor can be increased. Also, the maximum voltage limit applied to the transistor is increased due to increases in gate turn-on voltage and threshold voltage and a reduction in parallel conduction element. As a result, the power handling capability of the transistor can be improved, thus improving a high-power low-distortion characteristic and an isolation characteristic.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims priority to and the benefit of Korean Patent Application No. 2004-93330, filed Nov. 16, 2004, the disclosure of which is incorporated herein by reference in its entirety. BACKGROUND [0002] 1. Field of the Invention [0003] The present invention relates to a compound semiconductor switching device, which is an indispensable device for a compound semiconductor switch microwave monolithic integrated circuit (MMIC), and method of fabricating the same and, more specifically, to a transistor of a semiconductor device and method of fabricating the same, which lead to a reduction in insertion loss and increases in isolation and switching speed and are suitable for designing and fabricating a high-frequency control circuit with a high-power low-distortion characteristic. [0004] 2. Discussion of Related Art [0005] In general, mobile communication systems, such as mobile phones or wireless LANs, use GHz-band microwaves for co...

AI Technical Summary

Benefits of technology

This configuration reduces on-state insertion loss, increases off-state isolation, and improves power and distortion characteristics, enabling low-voltage operation with reduced chip size and production costs, thus enhancing the performance of high-power high-frequency switching devices.

Problems solved by technology

However, as capacitance caused by a Schottky contact formed between a gate electrode and the channel region increases, a high-frequency input signal is leaked from the Schottky contact, thus degrading the isolation of the transistor.

However, this method causes the chip size to increase, thus resulting in an increase in the cost of production.

However, when the circuit design techniques are used, a chip size increases owing to a transmission line for a λ / 4 transformer, a plurality of FETs, and an additional inductor or capacitor adjacent to a switching device, so that the cost of production is on the increase.

Further, when the device structure modification techniques are used, the cost of production of chips is raised like in the circuit design techniques because of an additional mask process and an increased distance between a source and a drain.

Images