ardhachaalak padaarth

suchaalak, ardhachaalak tatha kuchaalak ke baindon ki tulana

ardhachaalak (semiconductor) un padaarthon ko kehte hain jinki vidyut chaalakata chaalakon (jaise taaainba) se kam kintu achaalakon (jaise kaach) se adhik hoti hai. (aapekshik pratirodh praay: 10-5 se 108 om-meter ke beech) silikaun, jarmeniym, kaidamiym salfaaid, gailiym aarsenaaid ityaadi ardhachaalak padaarthon ke kuchh udaaharan hain. ardhachaalakon mein chaalan baind aur sanyojak baind ke beech ek 'baind gaip' hota hai jiska maan 0 se 6 elektraan-volt ke beech hota hai. (Ge 0.7 eV, Si 1.1 eV, GaAs 1.4 eV, GaN 3.4 eV, AlN 6.2 eV).

elektraanik yuktiyaaain banaane ke liye prayog kiye jaane vaale adhikaansh ardhachaalak aavart saarani ke samooh IV ke tatv (jaise silikaun, jarmeniym), samooh III aur V ke yaugik (jaise, gailiym aarsenaaid, gailiym naaitraaid, indiym enteemonaaid) antimonide), ya samooh II aur VI ke yaugik (kaidamiym teluraaid) hain. ardhachaalak padaarth ekal kristal ke roop mein ho sakte hain ya bahukristali paaudar ke roop mein ho sakte hain. vartamaan samay mein kaarbanik ardhachaalak (organic semiconductors) bhi banaae ja chuke hain jo praay: bahuchakri eromatik yaugik hote hain.

tattv samooh <font size="-1" antim kaksha mein
elektraanon ki salkya
Cd 12 2 e-
Al, Ga, B, In 13 3 e-
Si, C, Ge 14 4 e-
P, As, Sb 15 5 e-
Se, Te, (S) 16 6 e-

aadhunik yug mein prayukt tarah-tarah ki yuktiyon (devices) ke mool mein ye ardhachaalak padaarth hi hain. inse pehle daayod banaaya gaya aur fir traanjistar. isi ka haath pakadkar elektraanik yug ki yaatra shuroo hui. vidyut aur elektraaniki mein inki bahut badi bhoomika rahi hai. vigyaan ki jis shaakha mein ardhachaalakon ka adhyayan kiya jaata hai use thos avastha bhautiki (salid state fijiks) kehte hain.

ardhachaalakon ke vishesh gun

taap badhaane par ardhachaalakon ki vidyut chaalakata badhti hai, yeh gun chaalakon ke ulta hai. ardhachaalakon mein bahut se anya upayogi gun bhi dekhne ko milte hain, jaise kisi ek disha mein doosare disha ki apeksha aasaani se dhaara pravaah (arthaat bhinn-bhinn dishaaon mein vidyutachaalakata ka bhinn-bhinn hona). iske alaava niyantrit maatra mein ashuddhiyaaain daalkar (ek karod mein ek bhaag ya isse milta-julata) ardhachaalakon ki chaalakata ko kam ya adhik banaaya ja sakta hai. in ashuddhiyon ko milaane ki prakriya ko 'dopan' (doping) kehte hain. doping karke hi elektraanik yuktiyon (daayod, traanjistar, aaisi aadi) ka nirmaan kiya jaata hai. inki chaalakata ko baahar se lagaae gaye vidyut kshetr ya prakaash ke dvaara bhi parivrtit kiya ja sakta hai. yahaaain tak ki inki vidyut chaalakata ko taanakar (tensile force) ya dabaakar bhi badla ja sakta hai.

apne inheen gunon ke kaaran ye ardhachaalak prakaash evam anya vidyut sanketon ko aavardhit (emplifaai) karne waali yuktiyaaain banaane, vidyut sanketon se niyantrit svich (jaise beejeti, mausafet, esaseeaar aadi) banaane, tatha oorja parivrtak (dekhein, shakti elektraaniki) ke roop mein kaam karte hain. ardhachaalakon ke gunon ko samajhne ke liye kvaantam bhautiki ka sahaara liya jaata hai.

kuchh ardhachaalakon ka parichay

ardhachaalak yuktiyon ke nirmaan mein silikaun (Si) ka sabse adhik prayog hota hai. anya padaarthon ki tulana mein iske mukhya gun hain kachche maal ki kam laagat, nirmaan me aasaani aur vyaapak taapamaan parichaalan seema. vartamaan mein ardhachaalak yuktiyon ke nirmaan ke liye pehle silikaun ko kam se kam 300mm ki chaudaai ke baul ke nirmaan se kiya jaata hai, taaki is se itni hi chaudi vefar ban sake.

pehle jarmeniym (Ge) ka prayog vyaapak tha, kintu iske ushn atisanvedanasheelata ke karan silikaun ne iski jagah le li hai. aaj jarmeniym aur silikaun ke kudhaatu ka prayog aksar ativegashaali yuktiyon ke nirmaan me hota hai; I bi M ese yuktiyon ka pramukh utpaadak hai.

gailiam aarsenaaid (GaAs) ka prayog bhi vyaapak hai ativegashaali yuktiyon ke nirmaan mein, magar is padaarth ke chaude baul nahi ban paate, jiske kaaran silikaun ki tulana mein gailiam aarsenaaid se ardhachaalak yuktiyon ko banaana mehanga padata hai.

anya padaarth jinka prayog ya to kam vyaapak hai, ya un par anusandhaan ho raha hai:

  • silikaun kaarbaaid (SiC) ka prayog neele prakaash utsarjak daayod (L-E-di, LED) ke liye ho raha hai. pratikool vaataavaran, jaise uchch taapamaan ya atyaadhik aayanit vikirn, ke hone par iske upayog par anusandhaan ho raha hai. silikaun kaarbaaid se inpait daayod (IMPATT) ko bhi banaaya gaya hai.
  • indiym ke samaas, jaise indiym aarsenaaid, indiym entimonaaid aur indiym fausfaaid, ka bhi prayog L-E-di aur thos avastha lesar daayod me ho raha hai.
  • saur photo voltaayik sel ke nirmaan ke liye seleniym salfaaid par anusandhaan ho raha hai.

ardhchaalak 2 tarah kai hautai hai!

baahari kadiyaaain