슬라이드 1

Transcription

1 ICP/MS 를이용한고분자유기화합물의 direct 분석법 2015 년 10 월 16 일 제이케이씨

2 Classification of contamination Metals Ions Organics Particles

3 Contamination effects on device Generation of contamination Deterioration of device yield % of Total defects Particle + Metal Related : 80 % Total defects Reference : Reyes, J.D. Semiconductor International Oxide particle Metal short Contact defect Poly open Poly particle Metal defect Poly short Field defects Surface defect Scrach Misalignment Other

4 Contamination effects on device Contaminants Effect on Device Source Particle Metal ion Organic Native oxide Micro-roughness - Pattern defect - Insulation resistance - Ion implantation - Reduce carrier lifetime - Enhance leakage current - Decrease breakdown voltage - Cause drifts in threshold voltage - Affect oxide integrity - Induce surface micro-roughness - Haze degradation - Hydrophobicity - Electrical characteristic - Unintentional doping (P,B) - Silicon carbide, oxide quality Growth rate, post CVD defect rtc - Interfacial resistance - Gate oxide failure etc - Gate oxide failure - Decrease carrier mobility - Manual wafer handing - Raw material.chemical. Water. Feed Wafer - Process equipment material - Carriers and packaging boxes - Process chemical - Room air - Outgassing from construction materials - Coating, sealant, plastics, filter unit etc - Storage - Cleaning, etching and polishing process

5 Source of Metallic contamination in Semiconductor Process - Ultrapure water - Process : Ion implantation, CVD - All chemical used for : cleaning, drying, processing, etching and photolithography - Special materials : SOG, targets or metal film - Cleanrooms : metallic contamination in the air - Cleanroom components : construction com. Wafer carrier, gown, equip. benches - Gases : N 2, O 2, etc - Ozone generators - Reactor Device failure Must control

6 Introduction 1. 반도체공정에사용되는 P/R 용액의금속이온오염존재 - 전기적특성을왜곡시킴 - 최종제품의수율에영향을미침 - P/R에존재하는금속이온의농도를낮춰야됨 2. 현재 P/R spec. 및향후요구되는금속이온오염도 (Na, Mg, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn) - 현재허용되는금속이온농도 : 10 ~ 30ppb - 향후금속오염농도 : 10ppb 이하 3. P/R에존재하는금속이온의 Monitoring은매우중요하여주기적으로관리되어야함

7 Disadvantage normal analysis 1. 일반적인유기화합물전처리법 - 건식회화법 (Dry Ashing), 습식회화법 (Wet Ashing) - Pressure(Bomb) Digestion Method, Microwave Digestion등 2. 건식회화법 (Dry Ashing) 및습식회화법 (Wet Ashing) 의단점 - 전처리후분석이완료까지너무장시간이소요됨 - 휘발성이있는원소에대해서는유실현상이발생됨 (Hg, As, Zn, Sn) - 잠재적으로대기나용기, 전기로에서기인되는 2차오염에노출되어있음 - 일일분석처리량에한계가있어작업의효율이떨어짐 - 습식회화법에사용되는산류는 HNO 3, H 2 SO 4, HCLO 4, H 2 O 2 등의강산의사용으로작업자가위험에노출됨

8 Comparison of sample digestion process for organic analysis 구분건식회화법고압산분해법상압산분해법 장점 - 거의모든시료에적용가능 - 시료량에 대한 제한없음 - 단순한처리과정 - 정기적인관찰불 필요 단점 - 분해속도가느리고냉각시간이길다. - 고온회화로인한휘발성원소의손실 (Hg, As, Zn, Sn) - 시료오염 - 전력소모가많다. - 전처리시간의단축 : 1/10 이상 - 높은분해온도 : 270 이상 - 휘발성원소에대한회수율우수 - 공기중의불순물에대한시료오염최소화 - 시료량의제한 : 0.5g - 고가 ( 장치및기구 ) - 용기조립및세척불편 - 위험에 - 가장널리사용됨 - 시료량에대한제한없음 - 단순노동 - 시약및시료의추가가용이 - 관측용이 - 분해속도가느리다 - 재현성이나쁘다 - 고온에서분해되는시료를처리하기곤란하다 - 휘발성원소손실 - 분해과정의주의깊은관찰필요 - 위험에노출됨

9 Analytical Challenges 1. ICP/MS를이용한 P/R 및관련원료의 Direct 분석법 - NMP, PGME, PGMEA에희석하여 direct로분석을진행함 - 분석에사용된 Solvent의 impurities는분석결과에많은영향을미침 - 현재사용되고있는 solvent는 ( 주 ) 제이케이씨기준으로 <50ppt이하이므로 P/R분석에용의함 2. N-Methyl-2-Pyrrolidone(NMP) / C 5 H 9 NO - 물에잘녹는유기용제로반도체를비롯한제약, 석유화학, 고분자화학에널리사용되고있음 - 대분분의유기화합물은 NMP에안정적이며용해가쉽기때문에 ICP-OES ICP/MS를이용한유기물분석에광범위하게사용되고있음

10 Removal of Carbon 1. Carbon은 P/R, NMP, Polymer등에많이함유하고있음 2. Carbon은 Sampling cone등에 Deposition되어 cone의 orifice를막아감도저하현상을일으킴 3. Carbon은미량의 O 2 gas를공급하여 CO 2 gas상태로태워제거시키고, 금속이온만이 ICP/MS에서분석이됨 Aerosol Particles Molecule Atom Ion ICP/MS Ca(OH) 2 Ca Ca + 4C 5 H 9 NO + 27O 2 = 20CO H 2 O + 2N 2 Vaporization Dissociation Ionization 4. ICP/MS 는질량분석기이므로동일한질량을가진원소를동일한성분으로 인식함

11 Removal of Spectral Interference Potential Interference on Preferred Analyte Isotpes Analyte Mass Polyatomic ions B 10, C Mg C 2 Al C 14 N, 12 C 14 NH K ArH, 12 C 14 N 12 CH Ca Ar Ti C 16 O 2 Ti 46, 47, N 16 O 2 Ti 48, S 16 O, 32 S 16 OH Cr Ar 12 C Fe Ar 16 O Zn S 16 O 2 P/R에는 Carbon외 Hydrogen, Oxygen, Sulfur, Sulfonic acid등이포함됨

12 Instrumentation 실험목적 전처리환경 1. NMP희석분석법의적합성평가 2. 시료에서의회수율평가 3. 고분자유기화합물분석에서의정확성과정밀성평가 1. Clean room : class< DIW : 18.0MΩ이상, Metal 함량 : <10ppt 3. Solvent : NMP (JKC, <100ppt) 4. Bottle : LDPE 125mL 분석장치 1. ICP/MS : Thermo icap-qs 2. Quartz spray chamber, PFA nebulizer(100μl ), Operation condition 1. Cool plasma (Na, Mg, Al, K, Ca) 2. 수소 Mode (Cr, Fe, Ni, Cu, Zn) 전처리 condition 1. 정제된고순도 NMP 를이용하여 Calibration (Blank, 2.0ppb, 4.0ppb, 6.0ppb, 8.0ppb) 2. NMP 에용해후 Direct injection

13 Calibration curve Na Cr Fe Ni - 분석 method : Standard addition - Calibration result : R 2 = 1.000

14 Spike test result Con c(ppb) Sample + 2.0ppb Sample replication Na 52Cr 56Fe 58Ni Sample 20 회 Spike 3 회 Sample 20 회 Spike 3 회 Sample 20 회 Spike 3 회

15 Long time stability test result Con c(ppb) Na 24Mg 27Al 39K 40Ca 52Cr 55Mn 56Fe 58Ni 59Co 63Cu 64Zn Replication

16 Recovery test result Recovery(%) Na 24Mg 27Al 39K 40Ca 52Cr 55Mn 56Fe 58Ni 59Co 63Cu 64Zn Element

17 Conclusion 1. NMP를이용한희석분석법은 Organic 시료를별도의전처리없이직접분석가능한방법입니다. 2. 대분분의유기화합물은 NMP에안정적이며용해가쉽기때문에 ICP-OES, ICP/MS를이용한유기물분석에광범위하게사용되고있습니다. 3. NMP에희석되는고분자유기화합물은 Carbon을다량함유하고있으나, 분석시 O 2 를주입하여완전분해되어분석이이루어집니다. 4. Long time stability test 결과감도저하현상은크게발견되지않았고, 안정적으로분석됐습니다. 5. 표준액 spike test 결과 95%~105% 내외로우수한회수율을보였습니다. 6. NMP 희석분석법은고분자유기화합물을탄화법에서발생가능성이있는원소 유실및 2 차오염없이분석할수있는최적의방법입니다.

18 감사합니다.