Chinese Academy of Sciences

Zing Semiconductor Corporation

Shanghai Institute of Microsystem and Information Technology, Chinese Academy

Zhongying Xue

Miao Zhang

Xi Wang

Xing Wei

Jing Lan Chen

Deyuan Xiao

Zengfeng Di

Yun Liu

Minghao Li

Bo Zhang

Nan Gao

Jiantao Bian

Xun Wang

Tao Wei

Lin Ye

Zhan Li

Xiaohu Zheng

Da Chen

Pengfei Jia

The present application provides a method for verification of conductivity type of a silicon wafer. The method comprises measuring the resistivity of the silicon wafer to obtain a first resistivity, placing the silicon wafer under atmosphere of air for a predicted time period, measuring the resistivity of the silicon wafer to obtain a second resistivity, and determining conductivity type of the silicon wafer by comparing the first resistivity and the second resistivity. The method can be applied to a silicon wafer having a high resistivity such as higher than 500 ohmto rapidly and accurately determine conductivity type of the silicon wafer. Advantages of the method of the present application include accurate test results, easy operation, simple device requirement, and reduced cost.

Method for verification of conductivity type of silicon wafer

The invention provides a method of detecting crystallographic defects, comprising: sampling wafer of an ingot in complying with a predetermined wafer sampling frequency; identifying crystallographic defects of the wafer to show the crystallographic defects of the wafer; characterizing observation of the crystallographic defects of the wafer and extracting a value characterizing the crystallographic defects; through a result of characterizing the crystallographic defects, obtaining a radial distribution of density of the wafer and categorizing the crystallographic defects; and obtaining an isogram of the crystallographic defects of the wafer to show a crystallographic defect distribution of the whole ingot according to the value characterizing the crystallographic defects and categories of the crystallographic defects. It is no need to break the ingot to obtain the crystallographic defect distribution of the whole ingot, through which the technology for growing the ingot may be effectively adjusted to obtain the ingot with required characteristics of defect.

Method of detecting crystallographic defects and method of growing an ingot

The invention provides a measuring method of resistivity of a wafer, comprising: choosing a wafer to be measured, conducting a thermal treatment for the wafer to remove a thermal doner in the wafer, conducting an oxidation process for the wafer to form an oxidized surface on the wafer, and measuring resistivity of the wafer. In the method, firstly, the wafer is oxidized to get the oxidized surface, so as to restrict surface variation when placing the wafer in a later process. Therefore, the resistivity measurement of the wafer surface only slightly varies.

Measuring method of resistivity of a wafer

The present application provides a method for characterizing defects in silicon crystal comprising the following steps: etching a surface of the silicon crystal to remove a predicted thickness of the silicon crystal; conducting a LLS scanning to a surface of the etched silicon crystal to obtain a LLS map of the surface, a LSE size of defects, and defect bulk density; based on at least one of the LLS map of the surface, the LSE size of defects and the defect bulk density, determining a type of defect existing in the silicon crystal and/or a defect zone of each type of defect on the surface. By applying the method, the characterizing period and the characterizing cost can be reduced, plural defects such as vacancy, oxygen precipitate and dislocation can be characterized simultaneously, the characterizing accuracy can be enhanced, and the defect type and the defect zone can be determined with high reliability. In addition, the method can be applied to all crystal defect types, is easy to operate, and is an environmentally friendly method for determination of grown-in defects.

Method for characterizing defects in silicon crystal

The present invention provides a graphene structure having graphene bubbles and a preparation method for the same. The preparation method comprises: providing a substrate; forming a hydrogen terminated layer on a top surface of the substrate and a graphene layer disposed on a top surface of the hydrogen terminated layer; and placing a probe on the graphene layer and applying a preset voltage to the probe, to excite a part of the hydrogen terminated layer at a position corresponding to the probe to convert into hydrogen, the hydrogen causing the graphene layer at a position corresponding to the hydrogen to bulge, so as to form a graphene bubble enveloping the hydrogen.

Graphene structure having graphene bubbles and preparation method for the same

A method of making a silicon on insulator structure comprises: providing a bonded structure, the bonded structure comprises the first substrate, the second substrate and the insulating buried layer, the insulating buried layer is positioned between the first substrate and the second substrate; peeling off a layer of removing region of the first substrate from the bonded structure to obtain a first film; at a first temperature, performing a first etching to etch the first film to remove a first thickness of the first film; at a second temperature, performing a second etching to etch the first film to planarize the first film and remove a second thickness of the first film, the first temperature being lower than the second temperature, the first thickness being greater than the second thickness, and a sum of the first thickness and the second thickness being a total etching thickness of the first film.

Silicon on insulator structure and method of making the same

The present invention provides a method of making a silicon on insulator (SOI) structure, comprising steps of: providing a bonded structure, the bonded structure comprises a first substrate, a second substrate and an insulating buried layer, the insulating buried layer is positioned between the first substrate and the second substrate; peeling off a layer of removing region of the first substrate from the bonded structure to obtain a SOI structure; and processing the SOI structure with isothermal annealing technology at a pressure which is lower than atmospheric pressure.

Disclosed a heat shield structure for a single crystal production furnace, which is provided above a melt crucible of a single crystal production furnace and comprises an outer housing and a heat insulation plate disposed within the outer housing. A bottom outer surface of the outer housing faces an interior of the melt crucible, and an angle formed between a plane in which the heat insulation plate is located and a plane in which a bottom of the outer housing is located is an acute angle and faces an outer surface of single crystal silicon. The heat shield design is changed, a heat absorbing plate is additionally provided for transferring heat absorbed to the single crystal silicon, a heat channel is formed in the heat shield, so that a pulling rate is controlled, which improves radial mass uniformity of the single crystal silicon.

Heat shield structure for single crystal production furnace and single crystal production furnace

The present invention provides a method for preparing an ultra-thin material on insulator through adsorption by a doped ultra-thin layer. In the method, first, an ultra-thin doped single crystal film and an ultra-thin top film (or contains a buffer layer) are successively and epitaxially grown on a first substrate, and then a high-quality ultra-thin material on insulator is prepared through ion implantation and a bonding process. A thickness of the prepared ultra-thin material on insulator ranges from 5 nm to 50 nm. In the present invention, the ultra-thin doped single crystal film adsorbs the implanted ion, and a micro crack is then formed, so as to implement ion-cut; therefore, the roughness of a surface of a ion-cut material on insulator is small. In addition, an impurity atom strengthens an ion adsorption capability of the ultra-thin single crystal film, so that an ion implantation dose and the annealing temperature can be lowered in the preparation procedure, thereby effectively reducing the damage caused by the implantation to the top film, and achieving objectives of improving production efficiency and reducing the production cost.

Method for preparing ultra-thin material on insulator through adsorption by doped ultra-thin layer

The present invention provides a method for preparing a GOI chip structure, where, in the method, first, a SiGe on insulator (SGOI) chip structure is made by using a SMART CUT technology, and then, germanium condensation technology is performed on the SGOI chip structure, so as to obtain a GOI chip structure. Because the SGOI made by the Smart-Cut technology basically has no misfit dislocation in an SGOI/BOX interface, the threading dislocation density of the GOI is finally reduced. A technique of the present invention is simple, the high-quality GOI chip structure can be implemented, and the germanium condensation technology is greatly improved. An ion implantation technology and an annealing technology are quite mature techniques in the current semiconductor industry, so that such a preparation method greatly improves the possibility of wide use of the germanium concentration technology in the semiconductor industry.

Method for preparing GOI chip structure

A silicon/germanium (SiGe) heterojunction Tunnel Field Effect Transistor (TFET) and a preparation method thereof are provided, in which a source region of a device is manufactured on a silicon germanium (SiGe) or Ge region, and a drain region of the device is manufactured in a Si region, thereby obtaining a high ON-state current while ensuring a low OFF-state current. Local Ge oxidization and concentration technique is used to implement a Silicon Germanium On Insulator (SGOI) or Germanium On Insulator (GOI) with a high Ge content in some area. In the SGOI or GOI with a high Ge content, the Ge content is controllable from 50% to 100%. In addition, the film thickness is controllable from 5 nm to 20 nm, facilitating the implementation of the device process. During the oxidization and concentration process of the SiGe or Ge and Si, a SiGe heterojunction structure with a gradient Ge content is formed between the SiGe or Ge and Si, thereby eliminating defects. The preparation method according to the present invention has a simple process, which is compatible with the CMOS process and is applicable to mass industrial production.

Silicon-germanium heterojunction tunnel field effect transistor and preparation method thereof

The present invention discloses a method of fabricating high-mobility dual channel material based on SOI substrate, wherein compressive strained SiGe is epitaxially grown on a conventional SOI substrate to be used as channel material of PMOSFET; Si is then epitaixally grown on SiGe, and approaches such as ion implantation and annealing are employed to allow relaxation of part of strained SiGe and transfer strain to the Si layer thereon so as to form strained Si material as channel material of NMOSFET. With simple process and easy realization, this method can provide high-mobility channel material for NMOSFET and PMOSFET at the same time, well meeting the requirement of simultaneously enhancing the performance of NMOSFET and PMOSFET devices and therefore providing potential channel material for CMOS process of the next generation.

Method of fabricating high-mobility dual channel material based on SOI substrate

The present invention discloses a method of NiSiGe epitaxial growth by introducing Al interlayer, comprising the deposition of an Al thin film on the surface of SiGe layer, subsequent deposition of a Ni layer on Al thin film and then the annealing process for the reaction between Ni layer and SiGe material of SiGe layer to form NiSiGe material. Due to the barrier effect of Al interlayer, NiSiGe layer features a single crystal structure, a flat interface with SiGe substrate and a thickness of up to 0.3 nm, significantly enhancing interface performance.

Method of NiSiGe epitaxial growth by introducing Al interlayer

A Ge and Si hybrid material inversion mode GAA (Gate-All-Around) CMOSFET includes a PMOS region having a first channel, an NMOS region having a second channel and a gate region. The first channel and the second channel have a racetrack-shaped cross section and are formed of n-type Ge and p-type Si, respectively; the surfaces of the first channel and the second channel are substantially surrounded by the gate region; a buried oxide layer is disposed between the PMOS region and the NMOS region and between the PMOS or NMOS region and the Si substrate to isolate them from one another. In an inversion mode, the devices have hybrid material, GAA structure with the racetrack-shaped, high-k gate dielectric layer and metal gate, so as to achieve high carrier mobility, prevent polysilicon gate depletion and short channel effects.

Hybrid material inversion mode GAA CMOSFET

A Ge and Si hybrid material inversion mode GAA (Gate-All-Around) CMOSFET includes a PMOS region having a first channel, an NMOS region having a second channel and a gate region. The first channel and the second channel have a circular-shaped cross section and are formed of n-type Ge and p-type Si, respectively; the surfaces of the first channel and the second channel are substantially surrounded by the gate region; a buried oxide layer is disposed between the PMOS region and the NMOS region and between the PMOS or NMOS region and the Si substrate to isolate them from one another. In an inversion mode, current flows through the overall cylindrical channel, so as to achieve high carrier mobility, reduce low-frequency noises, prevent polysilicon gate depletion and short channel effects and increase the threshold voltage of the device.

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Shanghai, China

Zhongying Xue