晶體生長(zhǎng)模擬軟件FEMAG_CUSP磁場(chǎng)對(duì)8英寸半導(dǎo)體級(jí)硅晶體生長(zhǎng)的影響

1、晶體生長(zhǎng)模擬軟件晶體生長(zhǎng)模擬軟件FEMAGCUSP磁場(chǎng)對(duì)磁場(chǎng)對(duì)8英寸半導(dǎo)體級(jí)硅晶體生長(zhǎng)的影響英寸半導(dǎo)體級(jí)硅晶體生長(zhǎng)的影響ReportBruker ASCFEMAGSoft 2012FEMAGSoft 2012OBJECTIVEPROCESS CONDITIONCZ furnace - 8 inch diameter crystal, 24 inch diameter crucibleTo predict the impact of a CUSP magnetic field operating at 140 A with the neutral-axis located on the melt

2、 free surface.SIMULATION PROCESSThe growth process is modeled as Time dependent simulation taking in to account the transient effects taking place during the growth of the crystalPARAMETERS OBSERVEDThe concentration of the Oxygen in the melt and crystal.The concentration of the Phosphorous in the me

3、lt and crystalThe concentration of the Carbon in the melt and crystalFEMAGSoft 2012CRYSTAL RADIAL OXYGEN MEASUREMENT POSITIONSFEMAGSoft 2011PREDICTION OF RADIAL OXYGEN CONCENTRATION00,020,040,060,080,10,12012345678R adial O xygen C oncentration H =90m mR adial O xygen C oncentration H =90m mC U S PC

4、 U S PN o C U S PN o C U S PR adius (m )R adius (m )O xygen ppm aO xygen ppm a00,020,040,060,080,10,120123456789R adial O xygen C oncentration H =250 m mR adial O xygen C oncentration H =250 m mC U S PC U S PN o C U S PN o C U S PR adius (m )R adius (m )O xygen ppm aO xygen ppm a00,020,040,060,080,1

5、0,120123456789R adial O xygen C oncentration H =430m mR adial O xygen C oncentration H =430m mC U S PC U S PN o C U S PN o C U S PR adius (m )R adius (m )O xygen ppm aO xygen ppm a00,020,040,060,080,10,120123456789R adial O xygen C oncentration H =640m mR adial O xygen C oncentration H =640m mC U S

6、PC U S PN o C U S PN o C U S PR adius (m )R adius (m )O xygen ppm aO xygen ppm aFEMAGSoft 2012PREDICTION OF RADIAL OXYGEN CONCENTRATION00,020,040,060,080,10,12012345678R adial O xygen C oncentratio H =840m mR adial O xygen C oncentratio H =840m mC U S PC U S PN o C U S PN o C U S PR adius (m )R adiu

7、s (m )O xygen ppm aO xygen ppm a00,020,040,060,080,10,12012345678R adial O xygen C oncentration H =1070R adial O xygen C oncentration H =1070C U S PC U S PN o C U S PN o C U S PR adius (m )R adius (m )O xygen ppm aO xygen ppm a00,020,040,060,080,10,12012345678R adial O xygen C oncentration H =1290m

8、mR adial O xygen C oncentration H =1290m mC U S PC U S PN o C U S PN o C U S PR adius (m )R adius (m )O xygen ppm aO xygen ppm a00,020,040,060,080,10,12012345678R adial O xygen C oncentration H =1550 m mR adial O xygen C oncentration H =1550 m mC U S PC U S PN o C U S PN o C U S PR adius (m )R adius

9、 (m )O xygen ppm aO xygen ppm aFEMAGSoft 2012PREDICTION OF OXYGEN CONCENTRATION ALONG THE HEIGHT OF THE CRYSTAL0,20,40,60,811,21,41,60123456789 O xygen C oncentration variation in a V ertical D irectionO xygen C oncentration variation in a V ertical D irectionC U S PC U S PN o C U S PN o C U S PH ei

10、ght (m )H eight (m )O xygen ppm aO xygen ppm aFEMAGSoft 2012PREDICTION OF CARBON CONCENTRATION ALONG THE HEIGHT OF THE CRYSTALFEMAGSoft 2012PREDICTION OF PHOSPHOROUS CONCENTRATION ALONG THE HEIGHT OF THE CRYSTALFEMAGSoft 2012CUSP vs NOCUSP - OXYGEN CONCENTRATION - CRYSTALFEMAGSoft 2012CUSP vs NOCUSP

11、 - CARBON CONCENTRATION - CRYSTALFEMAGSoft 2012CUSP vs NOCUSP - PHOSPHOROUS CONCENTRATION-CRYSTAL FEMAGSoft 2011CUSP vs NO CUSP - PHOSPHORUS RESISTIVITY - CRYSTALFEMAGSoft 2011PREDICTION OF RADIAL PHOSPHORUS RESISTIVITYFEMAGSoft 2012NOCUSP VS CUSP TEMPERATURE IN THE MELT Animation Temperature-melt.a

12、vi FEMAGSoft 2012 NOCUSP vs CUSP MELT TURBULENT VISCOSITYAnimation Turbulent viscosity-melt.avi FEMAGSoft 2012NOCUSP vs CUSP-VELOCITY & STREAM FUNCTION Animation - psi-melt.avi FEMAGSoft 2012NOCUSP vs CUSP - OXYGEN IN THE MELT Animation - Oxygen-melt.avi FEMAGSoft 2012NOCUSP vs CUSP - PHOSPHOROUS IN

13、 THE MELT - 1Animation - Phosphorous-melt.avi FEMAGSoft 2012 NOCUSP vs CUSP- PHOSPHOROUS IN THE MELT - 2Animation - Phosphorous-melt2.avi FEMAGSoft 2012NOCUSP vs CUSP - CARBON IN THE MELT- 1Animation - Carbon-melt.avi FEMAGSoft 2012 NOCUSP vs CUSP - CARBON IN THE MELT - 2Animation - Carbon-melt2.avi

14、 FEMAGSoft 2012NOCUSP vs CUSP - OXYGEN IN THE CRYSTALAnimation - Oxygen-ppm.avi FEMAGSoft 2012 NOCUSP vs CUSP - PHOSPHOROUS IN THE CRYSTALAnimation - Phosphorous-cry.avi FEMAGSoft 2012CUSP vs NOCUSP - PHOSPHOROUS RESISTIVITY - CRYSTAL Animation Phos-resistivity.avi FEMAGSoft 2012NOCUSP vs CUSP - CAR

15、BON IN THE CRYSTALAnimation - Carbon-ppm.avi FEMAGSoft 2012EFFECT OF A CUSP MAGNETIC FIELD ON OXYGEN CONCENTRATIONThe following observations can be drawn:With a cusp magnetic field, the overall oxygen concentration in the crystal decreases stronglyThis is effect is more important in the lower part o

16、f the crystal, where oxygen concentration decreases from about 7 ppma down to 3 ppmaThis lower oxygen concentration is the result of:- a stronger turbulent effect (see the turbulent viscosity) below the solid/liquid interface when no cusp field is applied, thereby facilitating the transfer of oxygen

17、 from the bottom of the melt towards the solid-liquid interface;- a lower temperature along the bottom of the crucible when a cusp field is applied, leading to a lower oxygen dissolution in this region; this lower temperature appears as an additional consequence of the lower melt flow turbulence, th

18、e associated heat transfer reduction, and the resulting cooling down of the bottom of the melt FEMAGSoft 2012EFFECT OF A CUSP MAGNETIC FIELD ON OXYGEN CONCENTRATION (continued)This lower oxygen concentration is the result of:- a different flow configuration: with a cusp field, the main flow cell (al

19、so called a Proudman cell) extends farther from the axis and closer to the melt/gas interface, thereby facilitating oxygen evaporation, while without cusp field the main flow cell remains located under the solid/liquid interfaceThe radial segregation is not very different with or without cusp field,

20、 showing a strong radial segregation close to the crystal wall in both cases, as a consequence of the strong oxygen evaporation prevailing near the tri-junctionFEMAGSoft 2012EFFECT OF A CUSP MAGNETIC FIELD ON CARBON CONCENTRATIONThe following observations can be drawn:There is very little difference

21、 in carbon concentration with or without a magnetic fieldThe carbon concentration is almost uniform in the melt, whether or not a cusp field is applied. This concentration increases steadily as a consequence of the segregation effect taking place along the solidification interface FEMAGSoft 2012EFFE

22、CT OF A CUSP MAGNETIC FIELD ON PHOSPHORUS CONCENTRATIONThe following observations can be drawn:There is very little difference in phosphorus concentration with or without a magnetic field Our model considers phosphorus evaporation at the melt/gas interface. However, this effect is currently very sma

23、ll due to the applied evaporation parameters of phosphorusTherefore, such as for carbon, the phosphorus concentration is almost uniform in the melt, whether or not a cusp field is applied. Again this concentration increases steadily as a consequence of the segregation effect taking place along the s

24、olidification interfaceFEMAGSoft 2012PERSPECTIVESIn order to better analyze the effect of a cusp magnetic field on species concentration, the following aspects should be investigated: Performing the analysis with a locally adapted and finer meshes, in order to better resolve the dissolution and segr

25、egation boundary layers, and to better capture the radial segregation at the crystal wallPerforming simulations with a modified position of the cusp field: the neutral plane location should be optimized in order to get a more uniform oxygen distribution in the crystal (with a reduced axial segregati

26、on) Doing a parametric study of the carbon transfer process, more specifically oriented on the carbon transfer at the melt gas interface. In addition integrate the potential transformation of carbon into silicon carbide particles.Further investigating the effect of the cusp field on carbon and phosphorus distributions by tuning the material properties of these species. Indeed, in other p