目前智能壓力傳感器分為壓阻式和電容式兩大類。壓阻式壓力傳感器根據(jù)工藝技術(shù)不同分為：金屬應(yīng)變式；玻璃微熔式；擴(kuò)散硅；陶瓷壓阻；濺射薄膜式。

陶瓷電容式根據(jù)工藝要求和量程不同在電極的形狀和電極表面的處理上略有不同。根據(jù)應(yīng)用可大致分三類：

1、32mm直徑大膜片。（應(yīng)用于工業(yè)現(xiàn)場的監(jiān)控）

2、21mm直徑小膜片。（應(yīng)用于發(fā)動機(jī)機(jī)油壓力檢測）

3、16X16mm方形膜片。（應(yīng)用于汽車空調(diào)壓力檢測）

首先是壓阻式壓力傳感器

１：金屬應(yīng)變片式

金屬應(yīng)變技術(shù)是歷史最為悠久的傳感器技術(shù)。在各種壓力傳感器應(yīng)用中也是最早的。技術(shù)成熟，廣泛被中小企業(yè)所采用。主要應(yīng)用于中高壓力（20Bar－1000Bar）和超高壓（1000Bar以上）的測量。

在稱重傳感器上應(yīng)用金屬應(yīng)變計很多，應(yīng)變計具有溫漂小的優(yōu)點(diǎn)。同時靈敏度?。ㄒ话?/span>2mV/V）和橋路阻值小，使其應(yīng)用于壓力變送器尤其是4-20mA輸出的二線制變送器在電路設(shè)計上往往比較困難，對電路的要求比較高。隨著數(shù)字電路技術(shù)的發(fā)展這個問題已經(jīng)基本得到妥善解決。各大數(shù)字壓力變送IC廠商都已提供了較好的解決方案電路。另外要提到的是國內(nèi)很多企業(yè)對應(yīng)變計貼片工藝研究不夠深入，工藝上存在不足，造成應(yīng)變傳感器零點(diǎn)漂移，長期穩(wěn)定性不好以及抗過載能力不足。但是目前發(fā)展到現(xiàn)在，國內(nèi)及進(jìn)口的金屬應(yīng)變式傳感器基本沒有差別，在工藝和功能上都得到良好的解決。

２：玻璃微熔式

玻璃微熔技術(shù)由美國MSI公司于上個世紀(jì)90年代早期研發(fā)成功并開始批量生產(chǎn)。90年代中晚期被美國TI公司應(yīng)用于汽車工業(yè)。主要用于汽車EBD系統(tǒng)。近幾年開始應(yīng)用于缸內(nèi)直噴技術(shù)的發(fā)動機(jī)上。測量壓力范圍7Bar-700Bar。 有良好的可批量生產(chǎn)性，硅應(yīng)變計的生產(chǎn)技術(shù)現(xiàn)為國外公司所掌握。國內(nèi)目前有公司已在研發(fā)和小批量生產(chǎn)，產(chǎn)品的可靠性有待確認(rèn)。也有少數(shù)公司開始生產(chǎn)微熔壓力傳感器。

半導(dǎo)體硅片的溫度特性比較差，通常大于10%FS/100度，必須進(jìn)行溫度補(bǔ)償，補(bǔ)償方式通常有模擬補(bǔ)償和數(shù)字補(bǔ)償兩種方式。

３：擴(kuò)散硅式

擴(kuò)散硅技術(shù)是隨著上個世紀(jì)后期半導(dǎo)體微機(jī)電技術(shù)和其它材料及輔助生產(chǎn)技術(shù)的日益成熟漸漸發(fā)展起來的一種傳感器技術(shù)。同樣有良好的可批量生產(chǎn)性，但制造成本相對較高，設(shè)備投入相對較大，工藝流程相對較長。測量壓力范圍10Kpa -700Bar.國內(nèi)主要制造商寶雞麥克、恒通、南京高華等。目前較少應(yīng)用于汽車行業(yè)，多用于工業(yè)領(lǐng)域。但近年美國精量電子已開發(fā)出應(yīng)用與汽車領(lǐng)域的低成本擴(kuò)散硅充油壓力變送器。

４：陶瓷壓阻式

陶瓷壓阻技術(shù)也成熟與上個世紀(jì)末期，陶瓷本身的剛性決定了它非常合適做傳感器膜片材料，加之鐐系電阻材料延展特性與之配合是一種理想的傳感器技術(shù)選著。目前國內(nèi)外有眾多的公司生產(chǎn)。但在陶瓷材料燒結(jié)和鐐系電阻材料以及其他輔助材料和工藝上國內(nèi)公司和國外公司還是有很大的差距的。壓力測量范圍1Bar-700Bar，但不合適測量沖擊性高壓。

同樣有批量生產(chǎn)性，通用公司有應(yīng)用于汽車機(jī)油壓力測量領(lǐng)域。在50Bar以內(nèi)壓力測量較為廣泛。成本相對較低。

５：濺射薄膜式

濺射薄膜技術(shù)是上個世紀(jì)末隨著濺射技術(shù)的成熟而發(fā)展起來的新型技術(shù)?？梢岳斫鉃閼?yīng)變計技術(shù)借助新技術(shù)的發(fā)展。測量壓力范圍5Bar-1000Bar。

６：陶瓷電容式

陶瓷電容技術(shù)是利用平行板電容的電容值與板間距的的倒數(shù)成線性原理生產(chǎn)的一種電容傳感器，電容傳感器的校準(zhǔn)是利用電容的充放電時間的不同結(jié)合數(shù)字電路進(jìn)行的。該技術(shù)目前只有少數(shù)外國公司能夠進(jìn)行批量化生產(chǎn)。廣泛用于工業(yè)領(lǐng)域和汽車領(lǐng)域。

陶瓷電容生產(chǎn)技術(shù)的核心在于電極厚度1微米和電極間距20微米。陶瓷電容的過載能力優(yōu)于其他傳感器其技術(shù)。但是放大必須用數(shù)字電路。

At present, smart pressure sensors are divided into two categories: piezoresistive and capacitive. Piezoresistive pressure sensors are divided into: metal strain type; glass micro-melting type; diffusion silicon; ceramic piezoresistive; sputtering film type.


Ceramic capacitive type is slightly different in electrode shape and electrode surface treatment according to process requirements and measurement range. It can be broadly classified into three categories according to application.


1, 32mm large diameter diaphragm. (used in industrial field monitoring)


2, 21mm small diameter diaphragm. (applied to engine oil pressure test)


3, 16X16mm square diaphragm. (used in automobile air conditioning pressure test)


The first is piezoresistive pressure sensor.


1: metal strain gauge.

Metal strain technology is the oldest sensor technology. It is also the earliest application in all kinds of pressure sensors. Mature technology has been widely adopted by small and medium-sized enterprises. It is mainly applied to the measurement of medium high pressure (20 Ba 1000 1000) and ultra high pressure (above 1000Bar).

There are many metal strain gauges on weighing sensors, and the strain gauge has the advantage of small temperature drift. At the same time, the sensitivity is small (generally 2mV / V) and the bridge resistance is small, so it is difficult to apply it to the pressure transmitter, especially the 2-wire transmitter with 4-20mA output, in the circuit design, and the circuit requirements are higher. With the development of digital circuit technology, this problem has been basically solved. The major digital pressure transfer to IC manufacturers has provided a better solution circuit. In addition, many domestic enterprises have not done enough in-depth research on the strain gauge mounting process, and there are insufficient technology, resulting in zero drift of strain sensor, poor long-term stability and insufficient overload resistance. But at present, there is no difference between domestic and imported metal strain sensor, and it has been solved well in technology and function.

2: glass micro melting

Glass micro-melting technology was successfully developed by MSI in the early 1990s and began mass production. In the late 90s, it was used by the TI company in the automotive industry. It is mainly used in automobile EBD system. In recent years, it has been applied to the engine of direct injection technology. Measure pressure range 7Bar-700Bar. The production technology of silicon strain gauge is well controlled by foreign companies. At present, domestic companies have been developing and producing small quantities, and the reliability of products needs to be confirmed. A few companies are beginning to produce micro melt pressure sensors.

Semiconductor silicon wafer temperature characteristics are poor, usually greater than 10% FS / 100 degrees, must be compensated for temperature, compensation methods are usually analog compensation and digital compensation.

3: diffused silicon type

Diffused silicon technology is a kind of sensor technology developed gradually with the maturity of semiconductor micro-electromechanical technology, other materials and auxiliary production technology in the late last century. There is also good batch production, but the manufacturing cost is relatively high, equipment investment is relatively large, the process is relatively long. Measuring pressure range 10Kpa -700Bar. main domestic manufacturers Mike Baoji, Hengtong, Nanjing Gao Hua and so on. At present, it is seldom applied to the automotive industry, and is widely used in the industrial field. But in recent years, American precision electronics have developed low-cost diffused silicon oil-filled pressure transmitters for applications and automotive applications.

4: Ceramic piezoresistive

Ceramic piezoresistive technology is also mature with the end of the last century, the rigidity of ceramics itself determines that it is very suitable for sensor diaphragm materials, plus the ductility of praseodymium-based resistance materials with it is an ideal choice of sensor technology. At present, there are many companies at home and abroad. However, there is still a big gap between domestic and foreign companies in sintering ceramics, praseodymium resistance materials and other auxiliary materials and processes. The pressure range is 1Bar-700Bar, but it is not suitable to measure the impact pressure.

Also with mass production, General Company has been applied to the field of automotive oil pressure measurement. Pressure measurement is more extensive within 50Bar. The cost is relatively low.

5: sputtered film type

Sputtered film technology is a new technology developed at the end of last century with the development of sputtering technology. It can be understood that strain gauge technology relies on the development of new technology. Measure pressure range 5Bar-1000Bar.

6: ceramic capacitor type

Ceramic capacitance technology is a kind of capacitance sensor based on the principle that the reciprocal of the capacitance value of parallel plate capacitance and the distance between plates is linear. The calibration of capacitance sensor is carried out by combining the different charging and discharging time of capacitance with digital circuit. At present, only a few foreign companies can make mass production. Widely used in industrial and automotive fields.

The core of ceramic capacitor production technology is the electrode thickness of 1 microns and the electrode spacing of 20 microns. The overload capability of ceramic capacitors is superior to that of other sensors. But amplification must be done with digital circuits.