Wuhan Research Institute of Posts and Telecommunications

Yangtze Memory Technologies Co., Ltd.

Zhu Yang

Shaohua Yu

Qi Yang

Xiangning Wang

Chen Zuo

Jingjing Geng

Bin Yuan

Zhen Guo

Zongke Xu

Qiangwei Zhang

Xinxin Liu

Tao Zeng

Cai Li

Ivan B Djordjevic

Wu Liu

Jiajia Wu

William Shieh

Zhixue He

Xiaoyin Zhang

Shanhong You

Gangxiang Shen

Liming Cheng

Aspects of the disclosure provide methods for fabricating semiconductor devices. In some examples, a method for fabricating a semiconductor device includes forming a stack of layers having a first region and a second region. The stack of layers includes at least a first layer. The method then forms a hard mask layer on the stack of layers in the first region. Then, the method includes patterning the stack of layers in the second region of the semiconductor device. The patterning of the stack of layers in the second region removes a portion of the stack of layers in the second region, and exposes a side of the stack of layers. The method further includes covering at least the side of the stack of layers with a second layer that has a lower remove rate than the first layer, and then the method includes removing the hard mask layer.

Semiconductor device fabrication

The present disclosure provides a method for forming a three-dimensional (3D) memory. In an example, the method includes forming a stack structure having interleaved a plurality of stack first layers and a plurality of stack second layers, forming a stair in the stack structure, the stair having one of the stack first layers on a top surface, and forming a layer of sacrificial material having a first portion over a side surface of the stair and a second portion over the top surface of the stair. The method also includes partially removing the first portion of the layer of sacrificial material using an anisotropic etching process and removing a remaining portion of the first portion of the layer of sacrificial material using an isotropic etching process.

Methods for forming stairs in three-dimensional memory devices

Aspects of the disclosure provide semiconductor devices. For example, a semiconductor device includes a substrate having a first region and a second region along a first direction that is parallel to a main surface of the substrate. Then, the semiconductor device includes a memory stack that includes a first stack of alternating gate layers and insulating layers and a second stack of alternating gate layers and insulating layers along a second direction that is perpendicular to the main surface of the substrate. Further, the semiconductor device includes a joint insulating layer in the second region and a third stack of alternating gate layers and insulating layers in the first region between the first stack of alternating gate layers and insulating layers and the second stack of alternating gate layers and insulating layers.

Vertical memory devices

Embodiments of a three-dimensional (3D) memory device and fabrication methods thereof are disclosed. In an example, a method for forming a 3D memory device includes the following operations. A dielectric stack is formed to have interleaved sacrificial layers and dielectric layers. A stair is formed in the dielectric stack. The stair includes one or more sacrificial layers of the sacrificial layers and one or more dielectric layers of the dielectric layers. The stair exposes one of the sacrificial layers on a top surface and the one or more sacrificial layers on a side surface. An insulating portion is formed to cover the side surface of the stair to cover the one or more sacrificial layers. A sacrificial portion is formed to cover the top surface of the stair. The sacrificial portion is in contact with the one of sacrificial layers. The one or more sacrificial layers and the sacrificial portion are replaced with one or more conductor layers.

Method and structure for forming stairs in three-dimensional memory devices

Embodiments of three-dimensional (3D) memory devices and methods for forming the same are disclosed. In an example, a 3D memory device includes a substrate, a memory stack on the substrate, a plurality of channel structures each extending vertically through the memory stack, an isolation structure, and an alignment mark. The memory stack includes a plurality of interleaved conductive layers and dielectric layers. An outmost one of the conductive layers toward the substrate is a source select gate line (SSG). The isolation structure extends vertically into the substrate and surrounds at least one of the channel structures in a plan view to separate the SSG and the at least one channel structure. The alignment mark extends vertically into the substrate and is coplanar with the isolation structure.

Three-dimensional memory devices having isolation structure for source select gate line and methods for forming the same

Embodiments of a three-dimensional (3D) memory device and fabrication methods thereof are disclosed. In an example, a 3D memory device includes a memory stack having a plurality of stairs. Each stair may include interleaved one or more conductor layers and one or more dielectric layers. Each of the stairs includes one of the conductor layers on a top surface of the stair, the one of the conductor layers having (i) a bottom portion in contact with one of the dielectric layers, and (ii) a top portion exposed by the memory stack and in contact with the bottom portion. A lateral dimension of the top portion may be less than a lateral dimension of the bottom portion. An end of the top portion that may be facing away from the memory stack laterally exceeds the bottom portion by a distance.

A transmitting system, a receiving system, a transmitting method and a receiving method capable of implementing communications with multiple rates are described. The transmitting system comprises: a transmitting-side selection apparatus for selectively inputting input bit data to one of a first constellation mapping modulation apparatus and a second constellation mapping modulation apparatus based on a rate to be transmitted; the first constellation mapping modulation apparatus for performing a first constellation mapping modulation on the signal input thereto based on a selection made by the transmitting-side selection apparatus, so as to obtain a constellation-mapped signal; the second constellation mapping modulation apparatus for performing a second constellation mapping modulation on the signal input thereto based on the selection made by the transmitting-side selection apparatus, so as to obtain a constellation-mapped signal; and an OFDM modulation apparatus for performing an OFDM modulation on the constellation-mapped signal to obtain an OFDM-modulated signal for transmission.

Transmitting system and receiving system, and transmitting method and receiving method

A transmitting device, a receiving device, an optical communication system, and associated methods are provided. The transmitting device transmits an optical signal containing data, and comprises: an optical tone generator for generating at least one optical tone; at least one encoder for performing advanced coding on at least one data signal respectively, each of the at least one data signal carrying a part of the data; at least one mapper for performing high order modulation on the at least one coded data signal; and an up-converter for up-converting the at least one high-order-modulated data signal into the optical signal to be outputted through the at least optical tone. Thereby, high speed (e.g., over 1-Tb/s) transmission per single channel over a long-haul distance (e.g. over 1000-km) with error-free recovery may be achieved.

Optical communication system, device and method employing advanced coding and high modulation order

An optical communication system, a transmission apparatus and a reception apparatus, and a transmission method and a reception method are provided. The transmission apparatus transmits an optical signal, and comprises: at least one encoder for encoding at least one data signal, respectively; at least one first modulator for performing first modulation on the at least one encoded data signal, respectively, and generating at least one first modulated signal; at least one second modulator for performing second modulation, which is DFT-spread-OFDM modulation, on the at least one first modulated signal, respectively, and generating at least one second modulated signal; and an up-converter for up-converting the at least one second modulated signal into the optical signal to be transmitted. Thus, a PAPR of the optical OFDM transmission signal is decreased, a signal distortion caused by non-linearity of optical devices is reduced, and a reception quality of the signal is improved.

Optical communication system, transmission apparatus and reception apparatus, and transmission method and reception method

A bias voltage control system and method for an optical IQ modulator are disclosed. The optical IQ modulator includes an I-branch Mach-Zehnder Modulator (MZM) to which an I-branch bias voltage is applied, a Q-branch MZM to which a Q-branch bias voltage is applied, and an optical phase shifter to which an orthogonal bias voltage is applied. The system comprises a photo-detector converting at least a part of an optical signal output by the optical IQ modulator to an electrical signal; an analog-to-digital converter converting the electrical signal to a digital signal; and a digital signal processor superimposing a first dither signal and a second dither signal on the I-branch bias voltage and the Q-branch bias voltage respectively to generate a first order harmonic signal and a second order harmonic signal, and controlling the bias voltages according to powers of a DC component, and the first and second order harmonic signals.

Bias voltage control system and bias voltage control method

A reconfigurable optical add/drop multiplexer and a reconfigurable optical add/drop multiplexing method are provided. The reconfigurable optical add/drop multiplexer comprises: an optical processing unit for receiving a first optical signal containing a plurality of optical channels, processing the first optical signal to generate a second optical signal which is a part of the first optical signal, and outputting the second optical signal; and a coherent detection unit for performing a coherent detection on the second optical signal so as to separate from the second optical signal an optical channel contained therein, and outputting the optical channel. With the reconfigurable optical add/drop multiplexer and the reconfigurable optical add/drop multiplexing method, any number of degrees can be supported, and adding/dropping of an optical channel with any wavelength and any bandwidth to/from any direction can be achieved, so that requirements of being colorless, directionless, contentionless and gridless can be satisfied.

Reconfigurable optical add/drop multiplexer and reconfigurable optical add/drop multiplexing method

A modulation device and method, and a demodulation device and method are provided. The modulation device modulates plural baseband signals to generate an optical signal, and comprises: plural modulation units for modulating plural electrical carriers with different frequencies by using the baseband signals respectively, to generate corresponding electrical modulated signals; a synthesizer for synthesizing the electrical modulated signals to generate a single electrical synthesized signal; an optical modulation unit for modulating a single optical carrier by using the electrical synthesized signal to generate the optical signal, wherein signal components corresponding to the baseband signals in the optical signal are distributed on both sides of a carrier frequency of the optical carrier at a predetermined frequency interval. Thus, processing on a high-speed baseband signal may be divided into processing on multiple relatively low-speed baseband signals, overcoming a bottleneck caused by sampling rates of a digital-analog converter and an analog-digital converter.

Modulation device and modulation method, and demodulation device and demodulation method

A signal transmission and reception device and method are provided. The transmission method comprises generating multiple optical carriers from a basic optical carrier; modulating optical carriers, except for a predetermined optical carrier, in the optical carriers by using multiple data signals respectively, to generate multiple optical modulated signals; and synthesizing the multiple optical modulated signals and the predetermined optical carrier into a single optical signal, and transmitting the signal. The reception method comprises separating an optical signal into multiple optical carriers, the optical carriers having different frequencies and including a predetermined optical carrier; generating from the predetermined optical carrier multiple optical waves, frequencies of which correspond to frequencies of optical carriers, except for the predetermined optical carrier, in the multiple optical carriers; and demodulating the optical carriers, except for the predetermined optical carrier, in the multiple optical carriers by using the multiple optical waves respectively.

Growing community of inventors

Wuhan, China

Zhu Yang