Semiconductor siab sensors tuaj yeem muab faib ua ob pawg, ib qho yog raws li lub hauv paus ntsiab lus uas I-υ yam ntxwv ntawm semiconductor PN junction (los yog schottky junction) hloov nyob rau hauv kev ntxhov siab. Qhov kev ua tau zoo ntawm lub siab rhiab heev yog tsis ruaj khov thiab tsis tau tsim kho zoo heev. Lwm qhov yog lub sensor raws li semiconductor piezoresistive nyhuv, uas yog lub ntsiab ntau yam ntawm semiconductor siab sensor. Nyob rau hauv thaum ntxov hnub, semiconductor strain gauges feem ntau txuas nrog elastic ntsiab ua rau ntau yam kev ntxhov siab thiab strain ntsuas ntsuas. Xyoo 1960, nrog rau kev txhim kho ntawm semiconductor integrated circuit technology, semiconductor siab sensor nrog diffusion resistor li piezoresistive element tshwm. Hom kev ntsuas siab no muaj cov qauv yooj yim thiab txhim khu kev qha, tsis muaj qhov sib txawv txav, thiab lub zog rhiab heev thiab elastic keeb ntawm lub sensor yog kev sib xyaw, uas tsis txhob cuam tshuam kev lag luam thiab nkag mus thiab txhim kho kev ua haujlwm ntawm lub sensor.

Piezoresistive nyhuv ntawm semiconductor Semiconductor muaj ib tug yam ntxwv muaj feem xyuam rau sab nraud quab yuam, uas yog, lub resistivity ( sawv cev los ntawm lub cim ρ) hloov nrog cov kev ntxhov siab nws dais, uas yog hu ua piezoresistive nyhuv. Tus txheeb ze hloov ntawm resistivity nyob rau hauv qhov kev txiav txim ntawm chav tsev kev ntxhov siab yog hu ua piezoresistive coefficient, uas yog qhia los ntawm lub cim π. Qhia lej raws li ρ/ρ = π σ.

Qhov twg σ sawv cev rau kev ntxhov siab. Kev hloov pauv ntawm tus nqi tsis kam (R / R) tshwm sim los ntawm semiconductor tsis kam nyob rau hauv kev ntxhov siab feem ntau yog txiav txim siab los ntawm kev hloov ntawm kev tiv thaiv, yog li kev qhia ntawm piezoresistive nyhuv kuj tuaj yeem sau ua R / R = πσ.

Nyob rau hauv qhov kev txiav txim ntawm sab nraud quab yuam, qee qhov kev ntxhov siab (σ) thiab strain (ε) yog tsim nyob rau hauv semiconductor crystals, thiab kev sib raug zoo ntawm lawv yog txiav txim los ntawm Young's modulus (Y) ntawm cov khoom, uas yog, Y = σ / ε.

Yog hais tias cov nyhuv piezoresistive tau qhia los ntawm cov kab mob ntawm lub semiconductor, nws yog R / R = Gε.

G yog hu ua qhov rhiab heev ntawm lub siab sensor, uas sawv cev rau tus txheeb ze hloov ntawm cov nqi kuj nyob rau hauv chav tsev strain.

Piezoresistive coefficient lossis rhiab heev yog qhov tseem ceeb ntawm lub cev tsis zoo ntawm cov nyhuv semiconductor piezoresistive. Kev sib raug zoo ntawm lawv, ib yam li kev sib raug zoo ntawm kev ntxhov siab thiab kev nyuaj siab, yog txiav txim los ntawm Young's modulus ntawm cov khoom, uas yog, g = π y.

Vim yog anisotropy ntawm semiconductor crystals nyob rau hauv elasticity, Young's modulus thiab piezoresistive coefficient hloov nrog siv lead ua orientation. Qhov loj ntawm semiconductor piezoresistive nyhuv kuj zoo sib xws rau cov resistivity ntawm semiconductor. Qhov qis dua qhov resistivity, qhov me dua qhov rhiab heev. Cov nyhuv piezoresistive ntawm diffusion kuj yog txiav txim los ntawm cov siv lead ua orientation thiab impurity concentration ntawm diffusion kuj. Lub impurity concentration feem ntau yog hais txog qhov impurity concentration ntawm diffusion txheej.