Phosphorus ions have been implanted into silicon at an incident energy of 1.5 MeV to a dose of 1.5 × 10¹⁵ cm^-2 or 7.5 × 10¹⁵ cm^-2. Buried conductive layers have been formed in the Si substrate after annealing at 1050 °C for 20 s. IR reflection spectra in the wavenumber range 500-4000 cm^-1 were measured and interference fringes related to free-carrier plasma effects were observed. By detailed theoretical analysis and computer simulation of IR reflection spectra, the depth profile of the carrier concentration, the carrier mobility near maximum carrier concentration, and the carrier activation efficiency were obtained. The physical interpretation of the results and a critical discussion of the sensitivity of data fitted to variation in parameters are given.

Yuehui Yu;世昌 邹;Zhuyin Zhou;Guoqin Zhao

Materials Science and Engineering B: Solid-State Materials for Advanced Technology

1994-1

A triple self-aligned 2-bit/cell split-gate flash cell with a common select-gate (SG) for 2-bit is produced at 90-nm technology node. In this paper, scaling considerations of this novel split-gate flash are discussed. Firstly, SG-channel length scaling was discussed by evaluating the DIBL effect. It is revealed that aggressive scaling of SG-transistor is acceptable for sub-90-nm 2-bit/cell memory cell, because of the fully isolated SG-channel. Then, floating-gate (FG) coupling ratios are discussed. It is shown that coupling-gate (CG) to FG ratio is comparable to bit-line (BL) to FG ratio. Thirdly, source-side injection has been fully studied to obtain an efficient cell programming with a smaller constant I_DP. And an efficient cell programming condition is proposed for scaled 2-bit/cell memory with a constant I_DP of 1 μA/bit. Finally, impact of channel, LDD, and halo implants on I_R10 and I_R01 are discussed. The reliability characteristics are also presented. It was indicated that the scaled cells are very robust.

Zhaozhao Xu;Donghua Liu;Jun Hu;Wenjie Chen;Wensheng Qian;Weiran Kong;世昌 邹

Solid-State Electronics

2019-2

Ferroelectric thin films of Pb(Zr,Ti)O₃ (PZT) were fabricated on platinum coated silicon using the process of direct-current glow discharge assisted laser ablation. This process improved the crystallinity and ferroelectric behavior of the films. The c-axis oriented PZT films were obtained when deposited at 730°C with +80Ov discharge voltage. A possible mechanism for the improvement of the deposition process has been proposed.

Lerong Zheng;Chenglu Lin;W. Ping Xu;Shigeng Song;世昌 邹;T. P. Ma

Ferroelectrics

1997

A novel stacked class-E-like power amplifier (PA) topology with dual drain output power technique is proposed in this paper. Owing to the dual drain output power enhanced technique, the total output power is 1.25 times of the conventional class-E PA with single drain output. Meanwhile, benefited from the low ON resistance switch device on high resistance and trap-rich substrate of RFSOI technology, high PAE and low cost performance are also obtained. In particular, a differential dual drain output power class-E-like PA with an on-chip transformer based power combiner has been implemented in 0.18 um radio frequency silicon-on-insulator CMOS (RF SOI CMOS) technology. Experimental results show a peak PAE of 51% for the class-E-like PA with saturated output power of 29.6 dBm at 1.8 GHz 2.5 V supply voltage.

Jiangchuan Ren;Ruofan Dai;Jun He;Jun Xiao;Weiran Kong;世昌 邹

2018-6-29

The effects of total ionizing dose (TID) irradiation on the inter-device and intra-device leakage current in a 180-nm flash memory technology are investigated. The positive oxide trapped charge in the shallow trench isolation (STI) oxide is responsible for the punch-through leakage increase and punch-through voltage decrease. Nonuniform radiation-induced oxide trapped charge distribution along the STI sidewall is introduced to analyze the radiation responses of input/output (I/O) device and high voltage (HV) device. At low dose level, the inversion near the STI corner caused by the trapped charge occurs more easily due to the lower doping concentration in this region, which gives rise to the subthreshold hump effect. With total dose level increase, more charge at deep region of the STI oxide is accumulated, predominating the intra-device off-state leakage current. It has been discussed that the STI corner scheme and substrate doping profile play important roles on influencing the device's performance after radiation.

Bingxu Ning;正选 张;Zhangli Liu;Zhiyuan Hu;敏 陈;Dawei Bi;世昌 邹

Microelectronics Reliability

2012-1

A novel charge pump system with new regulation and clock generating techniques is proposed and verified in a 0.13µm CMOS process. Rather than generating the reference voltage by band-gap reference (BGR) and the detected voltage by high voltage divider in the conventional regulation, both voltage reference and division of proposed pump system are implemented by single new circuit. Besides, the conventional oscillator for clock input of charge pump system is removed while an adaptive clock generation scheme is introduced to reduce the power consumption and shrink the system size. The experiment results show that the pump system can produce a stable and smooth output with a small ripple, and the high output accuracy is comparable to the conventional solution equipped with BGR. Moreover, the power consumption of the pump controlling is reduced by about 80% while the size of pump system is decreased by about 25%. Therefore, the proposed regulated charge pump (RCP) is very suitable for ultra-low power and high precision applications, for example, the embedded nonvolatile memories (eNVMs).

Wenyi Zhu;Jianwei Jiang;Dianpeng Lin;Jun Xiao;Guangjun Yang;晓云 李;世昌 邹

IEICE Electronics Express

2019

The microstructure of high-T_c epitaxial YBCO superconducting thin films have been investigated using high-resolution transmission electron microscopy and scanning electron microscopy. It is found that the epitaxial growth of the film is closely related to not only deposition conditions, but also the surface quality of the substrate. The experimental results show that in epitaxial YBCO superconducting thin films grown on (100) SrTiO₃ single crystal substrates, the interface layer, defects, and undesirable orientations are the main elements which degrade the critical current density J_c of the film.

Yi Jie Li;Cong Xin Ren;Guo Liang Chen;世昌 邹

Science in China (Scientia Sinica) Series A

1993-7

The structures formed after the implantation of carbon in thermal SiO₂ and annealing present visible photoluminescence (PL) bands at room temperature. The peak wavelength and intensity of PL bands depend strongly on the temperature of annealing. In contrast, only very weak PL bands are observed after the implantation of argon in thermal SiO₂ and similar annealing. IR, Raman, SIMS and HRTEM were also used to characterize the microstructure of the carbon or argon implanted thermal SiO₂ films. These observations show that carbon aggregates are probably the origin of blue PL bands.

Y. H. Yu;Y. M. Lei;S. P. Wong;I. H. Wilson;世昌 邹

1999

A first order model of radiation induced narrow-channel effect (RINCE) is developed by applying charge conservation principle to calculate threshold voltage shift due to total ionizing dose (TID) irradiation. The model provides a way for extracting effective sheet charge density along shallow trench isolation (STI) sidewalls.

Zhiyuan Hu;Zhangli Liu;Hua Shao;正选 张;Bingxu Ning;敏 陈;Dawei Bi;世昌 邹

IEEE Transactions on Nuclear Science

2011-6

Radiation enhanced drain induced barrier lowering (DIBL) effect under different bias conditions was experimentally observed and verified by 3D simulation for deep submicron MOSFETs with shallow trench isolation (STI) oxides. The off-state leakage current increased significantly after total ionizing dose (TID) above 200 krad(Si) for PASS ,OFF and ON bias condition. The irradiated devices exhibited enhanced DIBL effect, that is the off-state leakage current increases with drain voltage and DIBL parameter increases with TID. The oxide trapped charge in the STI sidewall enhances the DIBL by decreasing the drain to gate coupling, enhancing the electric field near the STI corner, and increasing the surface potential of lowly doped substrate along STI sidewall. A simple dipole theory describing the enhanced DIBL phenomenon is introduced. The phenomenon is a result of the electrostatic effect, which concentrates drain field on channel into the source along shallow trench isolation oxide. Effective non-uniform charge distribution is applied in the 3D simulation for the radiation enhanced DIBL effect. Good agreement between experiment and simulation results is demonstrated.

Zhangli Liu;Zhiyuan Hu;正选 张;Hua Shao;Bingxu Ning;敏 陈;Dawei Bi;世昌 邹

IEEE Transactions on Nuclear Science

2011-6