Semiconductor germanium-base substrate material and preparation method thereof

Abstract

The invention provides a semiconductor germanium-base substrate material and a preparation method thereof and belongs to the technical field of manufacturing of super-large-scale integrated circuits. The method comprises the following steps of: forming a porous layer on a semiconductor substrate; arranging a semiconductor germanium sheet on the porous layer; and forming the semiconductor germanium-base substrate material on the porous layer. In the invention, by using a low dielectric constant of the porous layer and by forming the semiconductor germanium-base substrate material on the porouslayer, a coupling effect of a drain terminal on the potential of a trench by a buried layer can be effectively reduced, so a drain induced barrier lowering (DIBL) effect is effectively restrained, the parasitic capacitance of a source, a drain and a substrate can be reduced, and the speed characteristic of a device is improved. Meanwhile, the invention provides the preparation method of the semiconductor germanium-base substrate material. An ultra-thin semiconductor germanium material is prepared on a porous insulating layer by skillfully using an intelligent liftoff technology. The inventionsolves the problem of thinning during the application of a bonded and etched-back silicon-on-insulator (BESOI) technology and has the advantages of a separation by implantation of oxygen (SIMOX) technology and a bonding technology.

Description

technical field [0001] The invention belongs to the technical field of ultra-large-scale integrated circuit manufacturing technology, and in particular relates to a germanium-based substrate material and a preparation method thereof. Background technique [0002] With the continuous reduction of device size, the degradation of carrier mobility has become one of the key factors affecting the improvement of device performance. Compared with silicon materials, germanium materials have lower effective carrier mass, higher and more symmetrical low-field carrier mobility, narrow energy band width, and are compatible with silicon CMOS processes. Therefore, germanium-based devices are A promising direction for high-speed MOSFET devices. In order to achieve better device characteristics, the preparation of germanium-based substrate materials is also one of the current hot spots. [0003] Germanium on insulator (GeOI) has become one of the focuses of industry and academia due to the...

AI Technical Summary

Problems solved by technology

However, germanium and SiO 2 The interface contact characteristics are poor, which will degrade the corresponding device performance

For SOI devices, the drain will also affect the channel potential through the buried oxide layer, so the DIBL effect will be aggravated and the device performance will be further degraded

Although reducing the thickness of the buried layer can suppress the DIBL effect, it will increase the parasitic capacitance between the source drain and the substrate, degrading the performance of the device

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