A 3–10 GHz CMOS UWB Low-Noise Amplifier With ESD Protection Circuits

A low-power fully integrated low-noise amplifier (LNA) with an on-chip electrostatic-static discharge (ESD) protection circuit for ultra-wide band (UWB) applications is presented. With the use of a common-gate scheme with a ${rm g}_{rm m}$ -boosted technique, a simple input matching network, low noise figure (NF), and low power consumption can be achieved. Through the combination of an input matching network, an ESD clamp circuit has been designed for the proposed LNA circuit to enhance system robustness. The measured results show that the fabricated LNA can be operated over the full UWB bandwidth of 3.0 to 10.35 GHz. The input return loss $({rm S}_{11})$ and output return loss $({rm S}_{22})$ are less than ${-}8.3$ dB and ${-}9$ dB, respectively. The measured power gain $({rm S}_{21})$ is $11 pm 1.5$ dB, and the measured minimum NF is 3.3 dB at 4 GHz. The dc power dissipation is 7.2 mW from a 1.2 V supply. The chip area, including testing pads, is 1.05 mm$,times,$ 0.73 mm.      

Positive Bias Temperature Instability (PBTI) Characteristics of Contact-Etch-Stop-Layer-Induced Local-Tensile-Strained $hbox{HfO}_{2}$ nMOSFET

The positive bias temperature instability (PBTI) characteristics of contact-etch-stop-layer (CESL)-strained $hbox{HfO}_{2}$ nMOSFET are thoroughly investigated. For the first time, the effects of CESL on an $hbox{HfO}_{2}$ dielectric are investigated for PBTI characteristics. A roughly 50% reduction of $V_{rm TH}$ shift can be achieved for the 300-nm CESL $hbox{HfO}_{2}$ nMOSFET after 1000-s PBTI stressing without obvious $ hbox{HfO}_{2}/hbox{Si}$ interface degradation, as demonstrated by the negligible charge pumping current increase ($≪$ 4%). In addition, the $hbox{HfO}_{2}$ film of CESL devices has a deeper trapping level (0.83 eV), indicating that most of the shallow traps (0.75 eV) in as-deposited $ hbox{HfO}_{2}$ film can be eliminated for CESL devices.      

A Linearization Technique for RF Receiver Front-End Using Second-Order-Intermodulation Injection

A linearization technique is proposed in which low-frequency second-order-intermodulation $({rm IM}_{2})$ is generated and injected to suppress the third-order intermodulation $({rm IM}_{3})$. The proposed linearization technique is applied to both a low-noise amplifier (LNA) and a down-conversion mixer in an RF receiver front-end (RFE) working at 900 MHz. Fabricated in a 0.18$ mu{hbox{m}}$ CMOS process and operated at 1.5 V supply with a total current of 13.1 mA, the RFE delivers 22 dB gain with 5.3 dB noise figure (NF). The linearization technique achieves around 20 dB ${rm IM}_{3}$ suppression and improves the RFE's ${rm IIP}_{3}$ from $-$ 10.4 dBm to 0.2 dBm without gain reduction and noise penalty while requiring only an extra current of 0.1 mA.      

Electrical Instability of RF Sputter Amorphous In-Ga-Zn-O Thin-Film Transistors

Bias-temperature-stress (BTS) induced electrical instability of the RF sputter amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) was investigated. Both positive and negative BTS were applied and found to primarily cause a positive and negative voltage shift in transfer $(I _{rm DS} -V _{rm GS})$ characteristics, respectively. The time evolution of bulk-state density $(N _{rm BS})$ and characteristic temperature of the conduction-band-tail-states $(T _{G})$ are extracted. Since both values showed only minor changes after BTS, the results imply that observed shift in TFT $I _{rm DS} -V _{rm GS}$ curves were primarily due to channel charge injection/trapping rather than defect states creation. We also demonstrated the validity of using stretch-exponential equation to model both positive and negative BTS induced threshold voltage shift $(Delta V _{rm th})$ of the a-IGZO TFTs. Stress voltage and temperature dependence of $Delta V _{rm th}$ evolution are described.      

Performance Improvement of N-Type $hbox{TiO}_{x}$ Active-Channel TFTs Grown by Low-Temperature Plasma-Enhanced ALD

We report on performance improvement of $n$-type oxide–semiconductor thin-film transistors (TFTs) based on $hbox{TiO}_{x}$ active channels grown at 250 $^{circ}hbox{C}$ by plasma-enhanced atomic layer deposition. TFTs with as-grown $hbox{TiO}_{x}$ films exhibited the saturation mobility $(mu_{rm sat})$ as high as 3.2 $hbox{cm}^{2}/hbox{V}cdothbox{s}$ but suffered from the low on–off ratio $(I_{rm ON}/I_{rm OFF})$ of $hbox{2.0} times hbox{10}^{2}$. $hbox{N}_{2}hbox{O}$ plasma treatment was then attempted to improve $I_{rm ON}/I_{rm OFF}$. Upon treatment, the $hbox{TiO}_{x}$ TFTs exhibited $I_{rm ON}/I_{rm OFF}$ of $hbox{4.7} times hbox{10}^{5}$ and $mu_{rm sat}$ of 1.64 $hbox{cm}^{2}/hbox{V}cdothbox{s}$, showing a much improved performance balance and, thus, demonstrating their potentials for a wide variety of applications such as backplane technology in active-matrix displays and radio-frequency identification tags.      

1580-V–40-$hbox{m}Omegacdot hbox{cm}^{2}$ Double-RESURF MOSFETs on 4H-SiC $(hbox{000}bar{hbox{1}})$

Double-reduced-surface-field (RESURF) MOSFETs with $hbox{N}_{2}hbox{O}$ -grown oxides have been fabricated on the 4H-SiC $(hbox{000} bar{hbox{1}})$ face. The double-RESURF structure is effective in reducing the drift resistance, as well as in increasing the breakdown voltage. In addition, by utilizing the 4H-SiC $(hbox{000}bar{hbox{1}})$ face, the channel mobility can be increased to over 30 $hbox{cm}^{2}/hbox{V}cdothbox{s}$, and hence, the channel resistance is decreased. As a result, the fabricated MOSFETs on 4H-SiC $( hbox{000}bar{hbox{1}})$ have demonstrated a high breakdown voltage $(V_{B})$ of 1580 V and a low on-resistance $(R_{rm ON})$ of 40 $hbox{m}Omega cdothbox{cm}^{2}$. The figure-of-merit $(V_{B}^{2}/R_{rm ON})$ of the fabricated device has reached 62 $hbox{MW/cm}^{2}$, which is the highest value among any lateral MOSFETs and is more than ten times higher than the “Si limit.”      

A 0.55 V 60 dB-DR Fourth-Order Analog Baseband Filter

A 0.55 V supply voltage fourth-order low-pass continuous-time filter is presented. The low-voltage operating point is achieved by an improved bias circuit that uses different opamp input and output common-mode voltages. The fourth-order filter architecture is composed by two Active- ${rm G}_{rm m}{-}{rm RC}$ biquadratic cells, which use a single opamp per-cell with a unity-gain-bandwidth comparable to the filter cut-off frequency. The $-$ 3 dB filter frequency is 12 MHz and this is higher than any other low-voltage continuous-time filter cut-off frequency. The $-$3 dB frequency can be adjusted by means of a digitally-controlled capacitance array. In a standard 0.13 $mu{rm m}$ CMOS technology with ${V}_{THN}approx 0.25 {rm V}$ and ${V}_{THP}approx 0.3 {rm V}$, the filter operates with a supply voltage as low as 0.55 V. The filter $({rm total} {rm area}=0.47 {rm mm}^{2})$ consumes 3.4 mW. A 8 dBm-in-band IIP3 and a 13.3 dBm-out-of-band IIP3 demonstrate the validity of the proposal.      

Q-Band pHEMT and mHEMT Subharmonic Gilbert Upconversion Mixers

This letter makes a comparison between Q-band 0.15 $mu{rm m}$ pseudomorphic high electron mobility transistor (pHEMT) and metamorphic high electron mobility transistor (mHEMT) stacked-LO subharmonic upconversion mixers in terms of gain, isolation and linearity. In general, a 0.15 $mu{rm m}$ mHEMT device has a higher transconductance and cutoff frequency than a 0.15 $mu{rm m}$ pHEMT does. Thus, the conversion gain of the mHEMT is higher than that of the pHEMT in the active Gilbert mixer design. The Q-band stacked-LO subharmonic upconversion mixers using the pHEMT and mHEMT technologies have conversion gain of $-$7.1 dB and $-$0.2 dB, respectively. The pHEMT upconversion mixer has an ${rm OIP}_{3}$ of $-$12 dBm and an ${rm OP}_{1 {rm dB}}$ of $-$24 dBm, while the mHEMT one shows a 4 dB improvement on linearity for the difference between the ${rm OIP}_{3}$ and ${rm OP}_{1 {rm dB}}$. Both the chip sizes are the same at 1.3 mm $times$ 0.9 mm.      

AlN/GaN Insulated-Gate HEMTs With 2.3 A/mm Output Current and 480 mS/mm Transconductance

High-electron mobility transistors (HEMTs) based on ultrathin AlN/GaN heterostructures with a 3.5-nm AlN barrier and a 3-nm $hbox{Al}_{2}hbox{O}_{3}$ gate dielectric have been investigated. Owing to the optimized AlN/GaN interface, very high carrier mobility $(sim!!hbox{1400} hbox{cm}^{2}/hbox{V}cdothbox{s})$ and high 2-D electron-gas density $(sim!!kern1pthbox{2.7} times hbox{10}^{13} /hbox{cm}^{2})$ resulted in a record low sheet resistance $(sim !!hbox{165} Omega/hbox{sq})$. The resultant HEMTs showed a maximum dc output current density of $simkern1pt$2.3 A/mm and a peak extrinsic transconductance $g_{m,{rm ext}} sim hbox{480} hbox{mS/mm}$ (corresponding to $g_{m,{rm int}} sim hbox{1} hbox{S/mm}$). An $f_{T}/f_{max}$ of 52/60 GHz was measured on $hbox{0.25} times hbox{60} muhbox{m}^{2}$ gate HEMTs. With further improvements of the ohmic contacts, the gate dielectric, and the lowering of the buffer leakage, the presented results suggest that, by using AlN/GaN heterojunctions, it may be possible to push the performance of nitride HEMTs to current, power, and speed levels that are currently unachievable in AlGaN/GaN technology.      

Effects of Plasma-Induced Si Recess Structure on n-MOSFET Performance Degradation

Performance degradation of n-MOSFETs with plasma-induced recess structure was investigated. The depth of Si recess $(d_{R})$ was estimated from the experiments by using Ar gas plasmas. We propose an analytical model by assuming that the damage layer was formed during an offset spacer etch. A linear relationship between threshold voltage shift $(Delta V_{rm th})$ and $d_{R}$ was found. Device simulations were also performed for n-MOSFETs with various $(d_{R})$. Both $vertDelta V_{rm th}vert$ and off-state leakage current increased with an increase in $d_{R}$ . The increase in $vertDelta V_{rm th}vert$ becomes larger for smaller gate length. The results from device simulations are consistent with the analytical model. These findings imply that the Si recess structure induced by plasma damage enhances $V_{rm th}$-variability in future devices.      

Surface Deposition of Ionic Contaminants on Silicon Wafers in a Cleanroom Environment

The adsorption and desorption behaviors of ionic micro-contaminants on the silicon wafers in a cleanroom environment were investigated in this study. The experimental measurements showed that the surface density of ionic contaminants was significantly affected by both the exposure time and the properties of contaminants. The rate parameters of a kinetic model for surface deposition were determined by numerical optimization of fitting the experimental data on surface and ambient concentrations of airborne molecular contaminants (AMCs). Subsequently, the time-dependent deposition velocity and sticking coefficient of ionic species were obtained. The results showed that ${rm F}^{-}$, ${rm Cl}^{-}$, ${rm NO}_{3}^{-}$, ${rm SO}_{4}^{2-}$, ${rm Na}^{+}$, ${rm NH}_{4}^{+}$, ${rm K}^{+}$, and ${rm Mg}^{2+}$ were the major ionic microcontamination species on the wafer surfaces, with the adsorption rate constant and the sticking coefficient of ${rm K}^{+}$ ion being larger than those of other ionic contaminants. After the determination of sticking coefficients, the allowable wafer exposure durations and the maximum ambient concentrations of ionic species were exemplified based on the guideline recommended by the International Technology Roadmap for Semiconductors (ITRS).      

A 1 V 23 GHz Low-Noise Amplifier in 45 nm Planar Bulk-CMOS Technology With High-$Q$ Above-IC Inductors

A 23 GHz electrostatic discharge-protected low-noise amplifier (LNA) has been designed and implemented by 45 nm planar bulk-CMOS technology with high-$Q$ above-IC inductors. In the designed LNA, the structure of a one-stage cascode amplifier with source inductive degeneration is used. All high- $Q$ above-IC inductors have been implemented by thin-film wafer-level packaging technology. The fabricated LNA has a good linearity where the input 1 dB compression point $({rm IP}_{{-}1~{rm dB}})$ is ${- 9.5}~{rm dBm}$ and the input referred third-order intercept point $(P _{rm IIP3})$ is ${+ 2.25}~{rm dBm}$. It is operated with a 1 V power supply drawing a current of only 3.6 mA. The fabricated LNA has demonstrated a 4 dB noise figure and a 7.1 dB gain at the peak gain frequency of 23 GHz, and it has the highest figure-of-merit. The experimental results have proved the suitability of 45 nm gate length bulk-CMOS devices for RF ICs above 20 GHz.      

A Comparative NBTI Study of $hbox{HfO}_{2}$, $hbox{HfSiO}_{x}$, and SiON p-MOSFETs Using UF-OTF $I_{rm DLIN}$ Technique

The time, temperature, and oxide-field dependence of negative-bias temperature instability is studied in $hbox{HfO}_{2}/hbox{TiN}$, $ hbox{HfSiO}_{x}/hbox{TiN}$, and SiON/poly-Si p-MOSFETs using ultrafast on-the-fly $I_{rm DLIN}$ technique capable of providing measured degradation from very short (approximately microseconds) to long stress time. Similar to rapid thermal nitrided oxide (RTNO) SiON, $hbox{HfO}_{2}$ devices show very high temperature-independent degradation at short (submilliseconds) stress time, not observed for plasma nitrided oxide (PNO) SiON and $hbox{HfSiO}_{x}$ devices. $hbox{HfSiO}_{x}$ shows lower overall degradation, higher long-time power-law exponent, field acceleration, and temperature activation as compared to $hbox{HfO}_{2}$, which are similar to the differences between PNO and RTNO SiON devices, respectively. The difference between $ hbox{HfSiO}_{x}$ and $hbox{HfO}_{2}$ can be attributed to differences in N density in the $hbox{SiO}_{2}$ IL of these devices.      

Fast Characterization of Threshold Voltage Fluctuation in MOS Devices

Random microscopic fluctuations in the number and location of dopant atoms can cause a large variation in the threshold voltage $(V _{T})$ of a MOS device. In this paper, we present a technique for fast characterization of random threshold voltage mismatch in MOS devices. Our $V _{T}$ scatter characterization method measures threshold voltage shift by monitoring the change in gate-to-source voltage $V _{GS}$ for a fixed drain current $I _{DS}$ and drain-to-source voltage $V _{DS}$ . We present circuit schematics to characterize $V _{T}$ scatter by measuring $V _{GS}$ variation for a large set of devices arranged in an individually addressable array. We report experimental results of $V _{T}$ scatter measurement from test chips fabricated in 65-nm silicon-on-insulator and 65-nm bulk CMOS processes. We also measure and report the magnitude of local device current mismatch caused by $V _{T}$ fluctuation.      

Impacts of $hbox{N}_{2}$ and $hbox{NH}_{3}$ Plasma Surface Treatments on High-Performance LTPS-TFT With High-$kappa$ Gate Dielectric

Low-temperature polycrystalline-silicon thin-film transistors (LTPS-TFTs) with high- $kappa$ gate dielectrics and plasma surface treatments are demonstrated for the first time. Significant field-effect mobility $mu_{rm FE}$ improvements of $sim$86.0% and 112.5% are observed for LTPS-TFTs with $hbox{HfO}_{2}$ gate dielectric after $hbox{N}_{2}$ and $ hbox{NH}_{3}$ plasma surface treatments, respectively. In addition, the $hbox{N}_{2}$ and $ hbox{NH}_{3}$ plasma surface treatments can also reduce surface roughness scattering to enhance the field-effect mobility $mu_{rm FE}$ at high gate bias voltage $V_{G}$, resulting in 217.0% and 219.6% improvements in driving current, respectively. As a result, high-performance LTPS-TFT with low threshold voltage $V_{rm TH} sim hbox{0.33} hbox{V}$, excellent subthreshold swing S.S. $sim$0.156 V/decade, and high field-effect mobility $mu_{rm FE} sim hbox{62.02} hbox{cm}^{2}/hbox{V} cdot hbox{s}$ would be suitable for the application of system-on-panel.      

Integrated Hydrogen-Sensing Amplifier With GaAs Schottky-Type Diode and InGaP–GaAs Heterojunction Bipolar Transistor

New hydrogen-sensing amplifiers are fabricated by integrating a GaAs Schottky-type hydrogen sensor and an InGaP–GaAs heterojunction bipolar transistor. Sensing collector currents ( $I_{rm CN}$ and $I_{rm CH}$) reflecting to $hbox{N}_{2}$ and hydrogen-containing gases are employed as output signals in common-emitter characteristics. Gummel-plot sensing characteristics with testing gases as inputs show a high sensing-collector-current gain $(I_{rm CH}/I_{rm CN})$ of $≫hbox{3000}$. When operating in standby mode for in situ long-term detection, power consumption is smaller than 0.4 $muhbox{W}$. Furthermore, the room-temperature response time is 85 s for the integrated hydrogen-sensing amplifier fabricated with a bipolar-type structure.      

W-Band Active Down-Conversion Mixer in Bulk CMOS

A W-band (76–77 GHz) active down-conversion mixer has been demonstrated using low leakage (higher ${rm V}_{{rm T}}$) NMOS transistors of a 65-nm digital CMOS process with 6 metal levels. It achieves conversion gain of ${-}8$ dB at 76 GHz with a local oscillation power of 4 dBm (${sim-}2$ dBm after de-embedding the on-chip balun loss), and 3 dB bandwidth of 3 GHz. The SSB noise figures are 17.8–20 dB (11.3–13.5 dB after de-embedding on-chip input balun loss) between 76 and 77 GHz. ${rm IP}_{1{rm dB}}$ is ${-}6.5$ dBm and IIP3 is 2.5 dBm (${sim-}13$ and ${sim}-4$ dBm after de-embedding the on-chip balun loss). The mixer consumes 5 mA from a 1.2 V supply.      

Photosensitive Inverter and Ring Oscillator With Pseudodepletion Mode Load for LCD Applications

Photosensitive inverters and ring oscillators (ROs) with pseudodepletion mode loads (PDMLs) were integrated in LCD panels using conventional mass production processes. The delay time $(t_{rm pd})$ of five-stage ROs with PDML reduced from 204.3 $mu hbox{s}$ under dark to 16.3 $muhbox{s}$ under backlight illumination of 20 000 lx. The oscillation frequency exhibited a power-law dependence $(f_{rm osc} infty hbox{IL}^{gamma})$ on the backlight illuminance with the extracted fitting parameter $gamma = hbox{0.447}$ at room temperature.      

A 10-kV Monolithic Darlington Transistor With $beta_{ rm forced}$ of 336 in 4H-SiC

4H-SiC bipolar Darlington transistors with a record-high current gain have been demonstrated. The dc forced current gain was measured up to 336 at 200 $hbox{W/cm}^{2}$ ( $J_{C} = hbox{35} hbox{A/cm}^{2}$ at $V_{rm CE} = hbox{5.7} hbox{V}$) at room temperature. The current gain exhibits a negative temperature coefficient and remains as high as 135 at 200 $^{circ}hbox{C}$. The specific on-resistance is 140 $hbox{m}Omegacdothbox{cm}^{2}$ at room temperature and increases at elevated temperatures. An open-emitter breakdown voltage $(BV_{rm CBO})$ of 10 kV was achieved at a leakage current density of $≪hbox{1} hbox{mA/cm}^{2}$. The device exhibits an open-base breakdown voltage $(BV_{rm CEO})$ of 9.5 kV. The high current gain of SiC Darlington transistors can significantly reduce the gate-drive power consumption with the same forward-voltage drop as that of 10-kV SiC bipolar junction transistors, thus making the device attractive for high-power high-temperature applications.      

2 MHz AO $Q$ -switched ${rm TEM}_{00}$ Grazing Incidence Laser With 3 at.% Neodymium Doped Nd:YVO$_{4}$

We present a detailed experimental and theoretical study of the ultrahigh repetition rate AO $Q$ -switched ${rm TEM}_{00}$ grazing incidence laser. Up to 2.1 MHz $Q$-switching with ${rm TEM}_{00}$ output of 8.6 W and 2.2 MHz $Q$ -switching with multimode output of 10 W were achieved by using an acousto-optics $Q$ -switched grazing-incidence laser with optimum grazing-incidence angle and cavity configuration. The crystal was 3 at.% neodymium doped Nd:YVO$_{4}$ slab. The pulse duration at 2 MHz repetition rate was about 31 ns. The instabilities of pulse energy at 2 MHz repetition rate were less than ${pm}6.7hbox{%}$ with ${rm TEM}_{00}$ operation and ${pm}3.3hbox{%}$ with multimode operation respectively. The modeling of high repetition rate $Q$-switched operation is presented based on the rate equation, and with the solution of the modeling, higher pump power, smaller section area of laser mode, and larger stimulated emission cross section of the gain medium are beneficial to the $Q$-switched operation with ultrahigh repetition rate, which is in consistent with the experimental results.