Rau cov fais fab tuag, cov tsav tam sim no feem ntau yog ntau pua pua lub suab cim los yog ntau dua, thiab qhov ceev nrawm ntawm PN hlav yog loj heev, yog li qhov kub siab ntawm PN hlav dhau heev lawm. Rau ntim thiab daim ntawv thov, yuav ua li cas kom tsis txhob thermal resistance ntawm cov khoom, yog li ntawd lub tshav kub generated los ntawm PN hlav yuav tsum tau dissipated sai li sai tau, tsis tsuas yog yuav txhim kho cov saturation tam sim no ntawm cov khoom, los txhim kho lub luminous efficiency ntawm cov khoom , tab sis kuj txhim kho txoj kev cia siab thiab lub neej ntawm qhov khoom.
Yuav kom txo tau thermal tsis kam ntawm qhov khoom, qhov xaiv cov khoom ntim yog qhov tseem ceeb, xws li cov cua kub dab, nplaum, thiab lwm yam, thermal ua haujlwm ntawm txhua qhov khoom tsawg tsawg, uas yog, thermal conductivity yuav tsum yog qhov zoo. Qhov thib ob, cov qauv tsim yuav tsum tsim nyog, lub thermal conductivity ntawm cov ntaub ntawv yuav tsum sib txuas ua ke, thiab kev thermal kev sib txuas ntawm cov ntaub ntawv zoo, tsis txhob tso cov cua sov ntawm lub qhov kub thawm lub tshav kub thiab ua kom lub cua sov tawm ntawm lub sab hauv txheej txheej.
Nyob rau tib lub sij hawm, nws yog ib qhov tsim nyog los xyuas kom meej tias lub cua sov yog dissipated nyob rau hauv lub sij hawm raws li lub pre-tsim cua sov dissipation channel.