压阻式金刚石压力微传感器的制作与测试

由于金刚石薄膜具有优良的高温压阻特性，适合于制作高温压力传感器。在Φ50mm(100)硅单晶衬底上用热丝CVD法生长本征多晶金刚石薄膜作为绝缘隔离层，通过掩模选择性生长法得到掺硼金刚石薄膜电阻条，再经金属化处理和腐蚀硅压力腔，得到了压阻式金刚石压力微传感器的原型器件。对该器件的压力输出特性测量表明，输出电压一压力曲线线性较好，重复性好．常温下灵敏度高。     

多孔硅微细加工及其在微型传感器中的应用（二）

多孔硅微细加工的压阻压力传感器 微型压力传感器是在60年代末出现的,微细加工技术就是从此开始发展的。上面所述的各向异性化学腐蚀、电化学腐蚀和硅片直接融结等都已用来制造微型压阻压力传感器。微型压阻压力传感器尚需解决的问题是制造工艺太复杂、生产成本太高以及不易制造高灵敏的微压传感器等。针对这种情况,本文     

硅压阻压力传感器的近况和应用

硅具有显著的压阻效应,是制造硅压阻压力传感器的理想材料.用硅制成的压力传感器具有灵敏度高、动态响应快、测量精度高、稳定性好、工作温度范围宽、易于小型化和进行批量生产、使用方便等特点.本文综述硅压阻压力传感器的最近发展,产品制造用的新技术、性能特点、发展水平;概述硅压阻压力传感器的应用,并对我国硅压阻压力传感器的发展提出了一些看法.     

多晶硅压力传感器的研制

<正> 一、引言 多晶硅作为一种压阻材料,可以通过化学汽相淀积工艺淀积在陶瓷,玻璃,SiO_2,Si_3N4等绝缘材料上,从而制造出一种SOI结构的压力传感器,选种特性为高温压力传感器和更为灵敏的触敏传感器提供可靠的工艺基础。 多晶硅压力传感器避免了扩散型压力传感器的pn结漏电问题,展宽了器件的工作温度范围,高温可达200℃。同时多晶硅电阻的温度系数随掺杂浓度可调,在一定掺杂水平可制造     

介观压阻型微压力传感器设计

运用共振隧穿双势垒（DBRT）结构中的一种压阻效应原理-介观压阻效应,用GaAs／AlAs／InGaAs DBRT结构薄膜作为敏感元件,设计了一个周边固支平膜片结构的压力传感器。并对介观压阻和普通压阻灵敏度的量级作出了比较,验证了介观压阻效应原理,可以提高压力传感器的灵敏度,为制造基于介观压阻效应的新型超敏感型传感器提供了一定的理论依据。     

介观压阻型微压力传感器设计

运用共振隧穿双势垒(DBRT)结构中的一种压阻效应原理一介现压阻效应,用GaAsdAIAs/InGaAs DBRT结构薄膜作为敏感元件,设计了一个周边固支平膜片结构的压力传感器.并对介观压阻和普通压阻灵敏度的量级作出了比较,验证了介观压阻效应原理,可以提高压力传感器的灵敏度,为制造基于介观压阻效应的新型超敏感型传感器提供了一定的理论依据.     

一种SOI高温压力传感器敏感芯片

从传感器的受力结构、能量转化结构和金属引线三个方面对SOI压阻式压力传感器芯片进行高温设计,计算出每个因素所造成的影响并与外部气压对传感器造成的影响进行对比,并给出了压阻的工艺尺寸和掺杂浓度。通过工艺制备和封装,研制出耐高温压力传感器芯片,常温压力测试结果表明传感器敏感芯片在常温下灵敏度较高,非线性误差在0.1%以下,迟滞性小于0.5%。高温下的性能测试结果表明,传感器可以用于350℃恶劣环境条件下的压力测量,为压阻式高温压力芯片的研制提供了参考。     

压力传感器芯片版图设计中若干重要问题（1）

详细讨论了压阻型压力传感器设计中若刊重要问题，这些问题是合理利用压阻系数和膜上的应用，电阻条的布置和设计以及可靠性。     

硅压力传感器芯片设计分析与优化设计

用弹性力学和板壳力学理论分析了半导体硅压阻式压力传感器方形膜片的受力分布,为力敏电阻在应变膜上的布置提供依据;利用有限元分析方法和借助ANSYS仿真软件,对微型硅压阻式高温压力传感器应变膜进行了一系列的分析和计算机模拟,探讨了传感器方形应变膜简化应力模型的合理性以及温度对应力差分布的影响,得到了直观可靠的结果。     

一种新型MEMS压阻式SiC高温压力传感器

提出采用SiC材料来构造特殊环境下使用的MEMS压阻式高温压力传感器。分析了国际上特种高温压力传感器发展的主流趋势和技术途径,根据该领域应用需求、SiC材料特点和成本的多方权衡,开发了压阻式SiC高温压力传感器。通过理论模型结合ANSYS软件进行敏感结构的仿真和设计,解决了SiC压力传感器加工工艺中材料刻蚀、耐高温金属化、敏感电阻制备等关键技术难点,最终加工形成SiC高温压力传感器芯片。经过高温带电测试,加工的SiC压力传感器能够在550℃的环境温度下、700 kPa压力范围内输出压力敏感信号,传感器非线性指标达到1.054%,芯片灵敏度为0.005 03 mV/kPa/V,证明了整套技术的有效性。     

Rational Design of All Resistive Multifunctional Sensors with Stimulus Discriminability

A rational approach is proposed to design soft multifunctional sensors capable of detection and discrimination of different physical stimuli. Herein, a flexible multifunctional sensor concurrently detecting and distinguishing minute temperature and pressure stimuli in real time is developed using electrospun carbon nanofiber (CNF) films as the sole sensing material and electrical resistance as the only output signal. The stimuli sensitivity and discriminability are coordinated by tailoring the atomic- and device-level structures of CNF films to deliver outstanding pressure and temperature sensitivities of ? 0.96 kPa^?1 and ? 2.44%  ° C^?1, respectively, enabling mutually exclusive sensing performance without signal cross-interference. The CNF multifunctional sensor is considered the first of its kind to accomplish the stimulus discriminability using only the electrical resistance as the output signal, which is most convenient to monitor and process for device applications. As such, it has distinct advantages over other reported sensors in its simple, cost-effective fabrication and readout system. It also possesses other invaluable traits, including good bending stability, fast response time, and long-term durability. Importantly, the ability to simultaneously detect and decouple temperature and pressure stimuli is demonstrated through novel applications as a skin-mountable device and a flexible game controller.     

Micromachined chromium nitride thin-film pressure sensor for high temperature applications

The fabrication and characteristics of a micromachined chromium nitride (Cr-N) thin-film pressure sensor with high overpressure tolerance for high temperature applications are presented. The proposed pressure sensor consists of a Cr-N thin-film, patterned after a Wheatstone bridge configuration, and then sputter-deposited onto thermally oxidised Si membranes with a buried cavity for overpressure tolerance and an Al interconnection layer. This device is very suitable for high temperature integrated pressure sensors.     

Carbonized Silk Nanofiber Membrane for Transparent and Sensitive Electronic Skin

Recent years have witnessed the explosive development of electronic skin. Highly sensitive pressure sensing is one of the primary abilities of electronic skin. To date, most of the reported skin‐like pressure sensors are based on nanomaterials and microstructured polydimethylsiloxane (PDMS) films, limiting their wide practical applications due to the unknown biotoxicity and the redundant fabrication procedure. A cost‐effective, large‐area‐capable, and biocompatible approach for fabrication of high‐performance skin‐like pressure sensors is highly desired. Silk fibroin (SF) is a natural protein that has recently drawn great attention due to its application as the substrate for flexible electronics. Here, the fabrication of skin‐like pressure sensors is demonstrated using SF‐derived active materials. Flexible and conformal pressure sensors can be fabricated using transparent carbonized silk nanofiber membranes (CSilkNM) and unstructured PDMS films through a cost‐effective and large‐scale capable approach. Due to the unique N‐doped carbon nanofiber network structure of CSilkNM, the obtained pressure sensor shows superior performance, including ultrahigh sensitivity (34.47 kPa^?1) for a broad pressure range, an ultralow detection limit (0.8 Pa), rapid response time (<16.7 ms), and high durability (>10 000 cycles). Based on its superior performance, its applications in monitoring human physiological signals, sensing subtle touch, and detecting spatial distribution of pressure are demonstrated.     

Synthetic Diamond for Intracavity Thermal Management in Compact Solid-State Lasers

The intracavity use of newly developed low-birefringence synthetic diamond for thermal management in compact solid-state lasers is examined both experimentally and theoretically. A comparison - using single-crystal natural diamond as a base line - is made between synthetic, single-crystal diamond types: chemical vapor deposition and high pressure/high temperature grown diamond. The synthetic diamond samples are shown to possess significantly lower birefringence than often occurs in natural single-crystal diamond while maintaining the excellent thermal management properties and low insertion loss of natural diamond. Low threshold, high efficiency laser operation is demonstrated in polarization sensitive cavities incorporating intracavity synthetic diamond using both doped-dielectric and semiconductor gain elements. In addition, finite element analysis is used to demonstrate the potential of diamond to reduce thermal distortion and stress in doped-dielectric disk lasers. A 15 W Nd:GdVO₄ disk laser utilizing diamond is demonstrated. These results highlight the potential of low birefringence synthetic diamond for intracavity thermal management applications in solid-state lasers.     

Flexible and Highly Sensitive Pressure Sensors Based on Bionic Hierarchical Structures

The rational design of high‐performance flexible pressure sensors attracts attention because of the potential applications in wearable electronics and human–machine interfacing. For practical applications, pressure sensors with high sensitivity and low detection limit are desired. Here, ta simple process to fabricate high‐performance pressure sensors based on biomimetic hierarchical structures and highly conductive active membranes is presented. Aligned carbon nanotubes/graphene (ACNT/G) is used as the active material and microstructured polydimethylsiloxane (m‐PDMS) molded from natural leaves is used as the flexible matrix. The highly conductive ACNT/G films with unique coalescent structures, which are directly grown using chemical vapor deposition, can be conformably coated on the m‐PDMS films with hierarchical protuberances. Flexible ACNT/G pressure sensors are then constructed by putting two ACNT/G/PDMS films face to face with the orientation of the ACNTs in the two films perpendicular to each other. Due to the unique hierarchical structures of both the ACNT/G and m‐PDMS films, the obtained pressure sensors demonstrate high sensitivity (19.8 kPa^?1, <0.3 kPa), low detection limit (0.6 Pa), fast response time (<16.7 ms), low operating voltage (0.03 V), and excellent stability for more than 35 000 loading–unloading cycles, thus promising potential applications in wearable electronics.     

RF—HFCVD生长高质量纳米金刚石薄膜

采用射频等离子体增强的热丝化学气相沉积 (RF HFCVD)技术在石英玻璃衬底上制备了高质量的纳米金刚石薄膜 .研究了衬底温度、反应气压及射频功率对金刚石膜的结晶习性和光学性质的影响 ,其最佳值分别为70 0℃、2× 133Pa和 2 0 0W .在该条件下金刚石成核密度达 10 11cm-2 ,经 1h生长即获得连续薄膜 ,其平均晶粒尺寸为 2 5nm ,表面粗糙度仅为 5 5 ,在近红外区域 (80 0nm处 )的光透过率达 90 % .     

Growth and Isolation of Large Area Boron‐Doped Nanocrystalline Diamond Sheets: A Route toward Diamond‐on‐Graphene Heterojunction

Many material device applications would benefit from thin diamond coatings, but current growth techniques, such as chemical vapor deposition (CVD) or atomic layer deposition require high substrate and gas‐phase temperatures that would destroy the device being coated. The development of freestanding, thin boron‐doped diamond nanosheets grown on tantalum foil substrates via microwave plasma‐assisted CVD is reported. These diamond sheets (measuring up to 4 × 5 mm in planar area, and 300–600 nm in thickness) are removed from the substrate using mechanical exfoliation and then transferred to other substrates, including Si/SiO₂ and graphene. The electronic properties of the resulting diamond nanosheets and their dependence on the free‐standing growth, the mechanical exfoliation and transfer processes, and ultimately on their composition are characterized. To validate this, a prototypical diamond nanosheet–graphene field effect transistor‐like (DNGfet) device is developed and its electronic transport properties are studied as a function of temperature. The resulting DNGfet device exhibits thermally activated transport (thermionic conductance) above 50 K. Below 50 K a transition to variable range hopping is observed. These findings demonstrate the first step towards a low‐temperature diamond‐based transistor.     

High electrical resistivity of CVD-diamond

Due to its combination of excellent thermo-mechanical properties and electrical properties such as the high electrical resistivity and high dielectric strength, diamond seems a promising material for specialized dielectric applications. Due to the great advances in the growth technology of diamond films by chemical vapour deposition (CVD) on e.g. Si-substrates, new applications can be expected in microelectronics. An important technological result for dielectric applications is that high electrical resistivity diamond films can be obtained after an appropriate heat treatment of the as-grown films.     

Polyelectrolyte Dielectrics for Flexible Low‐Voltage Organic Thin‐Film Transistors in Highly Sensitive Pressure Sensing

Organic thin‐film transistors (OTFTs) can provide an effective platform to develop flexible pressure sensors in wearable electronics due to their good signal amplification function. However, it is particularly difficult to realize OTFT‐based pressure sensors with both low‐voltage operation and high sensitivity. Here, controllable polyelectrolyte composites based on poly(ethylene glycol) (PEG) and polyacrylic acid (PAA) are developed as a type of high‐capacitance dielectrics for flexible OTFTs and ultrasensitive pressure sensors with sub‐1 V operation. Flexible OTFTs using the PAA:PEG dielectrics show good universality and greatly enhanced electrical performance under a much smaller operating voltage of ?0.7 V than those with a pristine PAA dielectric. The low‐voltage OTFTs also exhibit excellent flexibility and bending stability under various bending radii and long cycles. Flexible OTFT‐based pressure sensors with low‐voltage operation and superhigh sensitivity are demonstrated by using a suspended semiconductor/dielectric/gate structure in combination with the PAA:PEG dielectric. The sensors deliver a record high sensitivity of 452.7 kPa^?1 under a low‐voltage of ?0.7 V, and excellent operating stability over 5000 cycles. The OTFT sensors can be built into a wearable sensor array for spatial pressure mapping, which shows a bright potential in flexible electronics such as wearable devices and smart skins.     

Light‐Boosting Highly Sensitive Pressure Sensors Based on Bioinspired Multiscale Surface Structures

Pressure sensors have attracted tremendous attention because of their potential applications in the fields of health monitoring, human–machine interfaces, artificial intelligence, and so on. Improving pressure‐sensing performances, especially the sensitivity and the detection limit, is of great importance to expand the related applications, however it is still an enormous challenge so far. Herein, highly sensitive piezoresistive pressure sensors are reported with novel light‐boosting sensing performances. Rose petal–templated positive multiscale millimeter/micro/nanostructures combined with surface wrinkling nanopatterns endow the assembled pressure sensors with outstanding pressure sensing performance, e.g. an ultrahigh sensitivity (70 KPa^?1, <0.5 KPa), an ultralow detection limit (0.88 Pa), a wide pressure detect ion range (from 0.88 Pa to 32 KPa), and a fast response time (30 ms). Remarkably, simple light illumination further enhances the sensitivity to 120 KPa^?1 (<0.5 KPa) and lowers the detection limit to 0.41 Pa. Furthermore, the flexible light illumination offers unprecedented capabilities to spatiotemporally control any target in multiplexed pressure sensors for optically enhanced/tailorable sensing performances. This light‐control strategy coupled with the introduction of bioinspired multiscale structures is expected to help design next generation advanced wearable electronic devices for unprecedented smart applications.