Sumitomo Mitsubishi Silicon Corporation

Other

Sumco Corporation

Ichiro Shiono

Kenji Yamaguchi

Kazuki Mizushima

Masaharu Ninomiya

Hazumu Kougami

A semiconductor substrate manufacturing method has a first layer formation process, a second layer formation process, a heat treatment process, and a polishing process; in the first layer formation process, the thickness of the first SiGe layer is set to less than twice the critical thickness, which is the film thickness at which dislocations appear and lattice relaxation occurs due to increasing film thickness; in the second layer formation process, the Ge composition ratio of the second SiGe layer is at least at the contact face with the first SiGe layer or with the Si layer, set lower than the maximum value of the Ge composition ratio in the first SiGe layer, and moreover, a gradient composition region in at least a portion of which the Ge composition ratio increases gradually toward the surface is formed. By this means, the penetrating dislocation density is kept low, surface roughness is low, and worsening of roughness at the surface and at interfaces due to heat treatment in device manufacturing processes or similar is prevented.

Semiconductor substrate and field-effect transistor, and manufacturing method for same

In a semiconductor substrate, a field effect transistor, and methods for producing the same, in order to lower threading dislocation density and also to lower surface roughness, a step of repeating, a plurality of times, a process of epitaxially growing a SiGe gradient composition layer of which a Ge composition ratio is gradually increased from a Ge composition ratio of a base material and a process of epitaxially growing a SiGe constant-composition layer on the gradient composition layer at a final Ge composition ratio of the gradient composition layer, thereby depositing a SiGe layer of which a Ge composition ratio changes in a film deposition direction, in a step-like manner with a gradient, a heat treatment step of performing heat treatment at a temperature exceeding a temperature of the epitaxial growth either during or after formation of the SiGe layer, and a polishing step of polishing to remove irregularities on a surface of the SiGe layer which arise in the heat treatment after formation of the SiGe layer are included.

Method for producing semiconductor substrate, method for producing field effect transistor, semiconductor substrate, and field effect transistor

A semiconductor substrate, a field effect transistor and their manufacturing methods provided with, in order to lower penetrating dislocation density and reduce surface roughness to a practical level, an Si substrate, a first SiGe layeron the Si substrate, and a second SiGe layerarranged on the first SiGe layer either directly or with an Si layer in between; wherein, the first SiGe layer has a film thickness that is thinner than twice the critical film thickness, which is the film thickness at which dislocation occurs resulting in lattice relaxation due to increased film thickness, the Ge composition ratio of the second SiGe layer is at least lower than the intralayer maximum value of the Ge composition ratio in the first SiGe layer or in the first SiGe layer at the contact surface with the Si layer, and the second SiGe layer has an incremental composition region in which the Ge composition ratio gradually increases towards the surface at least in a portion thereof.

Semiconductor substrate, field-effect transistor, and their manufacturing method of the same

The present invention relates to a semiconductor substrate production method, field effect transistor production method, semiconductor substrate and field effect transistor which, together with having low penetrating dislocation density and low surface roughness, prevent worsening of surface and interface roughness during heat treatment of a device production process and so forth. A production method of a semiconductor substrate W, in which SiGe layersandare formed on an Si substrate, is comprised of a heat treatment step in which heat treatment is performed either during or after the formation of the SiGe layers by epitaxial growth, at a temperature that exceeds the temperature of the epitaxial growth, and a polishing step in which irregularities in the surface formed during the heat treatment are removed by polishing following formation of the SiGe layers.

Production method for semiconductor substrate and production method for field effect transistor and semiconductor substrate and field effect transistor

A semiconductor substrate, a field effect transistor, a method of forming a SiGe layer and a method of forming a strained Si layer using the same, and a method of manufacturing a field effect transistor are provided, which enable the threading dislocation density of the SiGe layer to be reduced and the surface roughness to be minimized. On top of a Si substrate is provided a SiGe buffer layer constructed of a plurality of laminated layers comprising alternating layers of a SiGe gradient composition layer in which the Ge composition ratio increases gradually from the Ge composition ratio of the base material, and a SiGe constant composition layer which is provided on top of the gradient composition layer and in which the Ge composition ratio is equal to that of the upper surface of the gradient composition layer.

Semiconductor substrate, field effect transistor, method of forming SiGe layer and method of forming strained Si layer using same, and method of manufacturing field effect transistor

Growing community of inventors

Tokyo, Japan

Ichiro Shiono