电子级磷酸的纯化精制技术发展现状与研究进展

doi:10.11949/0438-1157.20230655

摘要/Abstract

摘要：

电子级磷酸作为一种超高纯化学试剂，主要用于微电子行业中芯片的清洗与蚀刻，其纯度会显著影响电子元器件的成品率、电性能以及可靠性。然而，极低杂质(10^-9水平)的高端电子级磷酸，对于化工分离纯化技术的要求极高。从电子级磷酸在芯片清洗与蚀刻方面的应用出发，梳理了电子级磷酸产品的主要国内外标准，概述了杂质离子的主要分析监测方法。重点综述了电子磷酸的制备和纯化精制方法，特别是结晶法在磷酸深度净化方面的显著优势，最后，对电子级磷酸的净化技术发展做出了前景展望。

关键词: 电子级磷酸, 电子材料, 纯化, 结晶, 技术集成, 痕量杂质

Abstract:

As a kind of ultra-high purity chemical reagent, electronic grade phosphoric acid is mainly used for chip cleaning and etching in the microelectronics industry, and its purity will significantly affect the yield, electrical performance and reliability of electronic components. However, high-end electronic grade phosphoric acid with extremely low impurities (10^-9 level) has extremely high requirements for chemical separation and purification technology. Based on the application of electronic grade phosphoric acid in chip cleaning and etching, the main domestic and foreign standards of electronic grade phosphoric acid products are reviewed, and the main analysis and monitoring methods of impurity ions are summarized. The preparation and purification methods of electronic phosphoric acid are reviewed, especially the significant advantages of crystallization in purifying phosphoric acid. Finally, the prospect of purification technology of electronic phosphoric acid is prospected.

Key words: electronic grade phosphoric acid, electronic materials, purification, crystallization, technology integration, trace impurity

中图分类号:

TQ 026.5

余留洋, 刘书博, 贾晟哲, 马航, 万邦隆, 苏琦雯, 王静康, 汤伟伟, 贺豫娟, 龚俊波. 电子级磷酸的纯化精制技术发展现状与研究进展[J]. 化工学报, 2024, 75(1): 1-19.

Liuyang YU, Shubo LIU, Shengzhe JIA, Hang MA, Banglong WAN, Qiwen SU, Jingkang WANG, Weiwei TANG, Yujuan HE, Junbo GONG. Current status and research progress of purification technology of electronic grade phosphoric acid[J]. CIESC Journal, 2024, 75(1): 1-19.

图/表 21

图1 GaN表面在H3PO4溶液中的表面恢复过程[9]

Fig.1 Evolution of the GaN surface for different durations in H3PO4[9]

表1 国际半导体设备与材料组织标准（SEMI）对于湿电子化学品的纯度要求［10］

Table 1 The purity of wet electronic chemicals in Semiconductor Equipment Materials International（SEMI）［10］

级别	单项金属杂质	控制微粒粒径	颗粒数	IC集成度
SEMI-C1、C2	≤100 ppb	≥1 μm	≤25个/ml	64 K
SEMI-C7	≤10 ppb	≥0.5 μm	≤25个/ml	4 M
SEMI-C8	≤1 ppb	≥0.5 μm	≤5个/ml	256 M
SEMI-C12	≤0.1 ppb	≥0.2 μm	协定	16 G

表2 国际半导体设备与材料组织标准（SEMI）对于电子级磷酸的标准［11-12］

Table 2 Standard for electronic grade phosphoric acid in Semiconductor Equipment Materials International（SEMI）［11-12］

指标	SEMI指标
指标	Grade 1(G1)	Grade 2(G2)	Grade 3(G3)
chloride（Cl^-）/ppm	1	1	1
nitrate（NO $_{3}^{-}$ ）/ppm	5	5	5
sulfate（SO $_{4}^{2 -}$ ）/ppm	—	12	12
aluminum（Al）/ppb	500	300	50
antimony（Sb）/ppb	10000	3500	1000
arsenic（As）/ppb	50	50	50
barium（Ba）/ppb	—	—	50
cadmium（Cd）/ppb	—	450	50
calcium（Ca）/ppb	1500	1100	150
chromium（Cr）/ppb	200	200	50
cobalt（Co）/ppb	50	50	50
copper（Cu）/ppb	50	50	50
gold（Au）/ppb	300	150	50
iron（Fe）/ppb	2000	700	100
lead（Pb）/ppb	300	300	50
lithium（Li）/ppb	100	100	10
magnesium（Mg）/ppb	200	200	50
manganese（Mn）/ppb	100	100	50
nickel（Ni）/ppb	200	200	50
potassium（K）/ppb	1500	450	150
sodium（Na）/ppb	2500	500	250
strontium（Sr）/ppb	100	100	10
zinc（Zn）/ppb	2000	400	50
titanium （Ti）/ppb	300	300	50

表2 国际半导体设备与材料组织标准（SEMI）对于电子级磷酸的标准［11-12］

Table 2 Standard for electronic grade phosphoric acid in Semiconductor Equipment Materials International（SEMI）［11-12］

指标	SEMI指标
指标	Grade 1(G1)	Grade 2(G2)	Grade 3(G3)
chloride（Cl^-）/ppm	1	1	1
nitrate（NO $_{3}^{-}$ ）/ppm	5	5	5
sulfate（SO $_{4}^{2 -}$ ）/ppm	—	12	12
aluminum（Al）/ppb	500	300	50
antimony（Sb）/ppb	10000	3500	1000
arsenic（As）/ppb	50	50	50
barium（Ba）/ppb	—	—	50
cadmium（Cd）/ppb	—	450	50
calcium（Ca）/ppb	1500	1100	150
chromium（Cr）/ppb	200	200	50
cobalt（Co）/ppb	50	50	50
copper（Cu）/ppb	50	50	50
gold（Au）/ppb	300	150	50
iron（Fe）/ppb	2000	700	100
lead（Pb）/ppb	300	300	50
lithium（Li）/ppb	100	100	10
magnesium（Mg）/ppb	200	200	50
manganese（Mn）/ppb	100	100	50
nickel（Ni）/ppb	200	200	50
potassium（K）/ppb	1500	450	150
sodium（Na）/ppb	2500	500	250
strontium（Sr）/ppb	100	100	10
zinc（Zn）/ppb	2000	400	50
titanium （Ti）/ppb	300	300	50

表3 GB/T 28159—2011《电子级磷酸》质量标准

Table 3 Quality standard for Electronic Grade Phosphoric Acid in GB/T 28159—2011

项目	指标
项目	E1	E2
易氧化物（以H₃PO₄计）/%(质量分数)	≤0.005	≤0.001
硝酸盐（NO $_{3}^{-}$ ）/ppm	≤5	≤0.5
硫酸盐（SO $_{4}^{2 -}$ ）/ppm	≤10	≤5
氯化物（Cl^-）/ppm	≤1	≤0.5
铝（Al）/ppb	≤200	≤50
硼（B）/ppb	—	≤50
锑（Sb）/ppb	≤3000	≤300
砷（As）/ppb	≤100	≤20
钡（Ba）/ppb	≤100	≤20
镉（Cd）/ppb	≤100	≤20
钙（Ca）/ppb	≤1000	≤50
铬（Cr）/ppb	≤100	≤20
钴（Co）/ppb	≤100	≤20
铜（Cu）/ppb	≤50	≤20
镓（Ga）/ppb	≤100	≤10
金（Au）/ppb	≤100	≤10
铁（Fe）/ppb	≤300	≤50
铅（Pb）/ppb	≤100	≤20
锂（Li）/ppb	≤100	≤10
镁（Mg）/ppb	≤100	≤20
锰（Mn）/ppb	≤100	≤20
镍（Ni）/ppb	≤100	≤20
钾（K）/ppb	≤100	≤20
银（Ag）/ppb	≤100	≤20
钠（Na）/ppb	≤500	≤50
锡（Sn）/ppb	—	≤10
锶（Sr）/ppb	≤100	≤20
钛（Ti）/ppb	≤100	≤50
锌（Zn）/ppb	≤100	≤50

表3 GB/T 28159—2011《电子级磷酸》质量标准

Table 3 Quality standard for Electronic Grade Phosphoric Acid in GB/T 28159—2011

项目	指标
项目	E1	E2
易氧化物（以H₃PO₄计）/%(质量分数)	≤0.005	≤0.001
硝酸盐（NO $_{3}^{-}$ ）/ppm	≤5	≤0.5
硫酸盐（SO $_{4}^{2 -}$ ）/ppm	≤10	≤5
氯化物（Cl^-）/ppm	≤1	≤0.5
铝（Al）/ppb	≤200	≤50
硼（B）/ppb	—	≤50
锑（Sb）/ppb	≤3000	≤300
砷（As）/ppb	≤100	≤20
钡（Ba）/ppb	≤100	≤20
镉（Cd）/ppb	≤100	≤20
钙（Ca）/ppb	≤1000	≤50
铬（Cr）/ppb	≤100	≤20
钴（Co）/ppb	≤100	≤20
铜（Cu）/ppb	≤50	≤20
镓（Ga）/ppb	≤100	≤10
金（Au）/ppb	≤100	≤10
铁（Fe）/ppb	≤300	≤50
铅（Pb）/ppb	≤100	≤20
锂（Li）/ppb	≤100	≤10
镁（Mg）/ppb	≤100	≤20
锰（Mn）/ppb	≤100	≤20
镍（Ni）/ppb	≤100	≤20
钾（K）/ppb	≤100	≤20
银（Ag）/ppb	≤100	≤20
钠（Na）/ppb	≤500	≤50
锡（Sn）/ppb	—	≤10
锶（Sr）/ppb	≤100	≤20
钛（Ti）/ppb	≤100	≤50
锌（Zn）/ppb	≤100	≤50

图2 ICP-OES、ICP-MS和GFAAS的检测分析原理对比[13]

Fig.2 The comparison of ICP-OES、ICP-MS and GFAAS[13]

表4 ICP-MS、ICP-OES和GFAAS的详细比较［13］

Table 4 The detailed comparison of ICP-MS， ICP-OES and GFAAS［13］

项目	ICP-OES	ICP-MS	GFAAS
检出限	绝大部分元素很好	绝大部分元素非常杰出	部分元素非常杰出
样品分析能力	5~30个元素/（样品·min）	2~6 min/样品中所有元素	4 min/（样品·元素）
线性动态范围	约10⁵	约10⁸	约10²
固体溶解量（最大可容忍量）	2%~25%	0.1%~0.4%	>20%
可测元素数	>73	>75	>50
样品用量	多	少	很少
半定量分析	能	能	不能
同位素分析	不能	能	不能
日常操作	容易	容易	容易
方法实验开发	需专业技术	需专业技术	需专业技术
无人控制操作	能	能	能
易燃气体	无	无	无
操作费用	高	高	中等
基本费用	高	很高	中等/高

图3 黄磷制取磷酸两步法工艺流程图[17]

Fig.3 Process flow chart of two-step process for producing phosphoric acid from yellow phosphorus[17]

图4 湿法磷酸制备流程[27]

Fig.4 Wet process phosphoric acid concentrator flow sheet[27]

表5 热法和湿法路线生产1吨工业磷酸所需原料量及动力消耗量对比［3］

Table 5 Comparison of raw materials and power required to produce one ton of industrial phosphoric acid in thermal and wet routes［3］

工艺路线	原料及动力	消耗量
热法磷酸工艺	磷矿	3.0~3.4 t
	黏土	0.2~0.3 t
	焦炭	0.5~0.6 t
	工艺用水	40 m³
	冷却用水	120 m³
	电力	5700~6000 kW·h
湿法磷酸工艺	磷矿	2.6~3.5 t
	硫酸	2.4~2.9 t
	工艺用水	3.6~52 m³
	冷却用水	100~150 m³
	电力	120~180 kW·h
	蒸汽	0.2~2.4 t

图5 电子级磷酸的深度净化技术[30-32]

Fig.5 Deep purification technology of electronic grade phosphoric acid[30-32]

图6 Marathon C树脂对U（Ⅳ）、Mn（Ⅱ）、Cu（Ⅱ）、Zn（Ⅱ）和Cd（Ⅱ）吸附效率和吸附容量的影响[30]

Fig.6 Effects of Marathon C resin on adsorption efficiency and capacity of U(Ⅳ), Mn(Ⅱ), Cu(Ⅱ), Zn(Ⅱ) and Cd(Ⅱ)[30]

图7 P-15萃取剂提纯湿法磷酸流程图[44]

Fig.7 Flow chart of P-15 extractant purification of wet phosphoric acid[44]

表6 溶剂萃取法去除磷酸中杂质离子的对比

Table 6 Comparison of removal of impurity ions from phosphoric acid by solvent extraction

萃取元素	萃取剂	O∶A	提取效率/%	文献
I	煤油	1∶2	99.25	[45]
I	西甲硅油	3∶1	95.00	[46]
F	TBP和SIO	1∶5	98.40	[47]
Mg	PN-1	4∶1	89.09	[48]
U和Ree	N-propylpropan-1-amine	1∶1	U: 95.30 Ree: 98.70	[49]
Cd	DIBDPi	1∶1	86.00	[50]
Cd	C₁₁H₁₈N₂O	1∶1	98.60	[51]
Cd	D₂EHDTPA	1∶1	96.00	[52]
Fe	TBP和煤油	1∶1	100	[43]

图8 H3PO4-H2O体系相图[1]

Fig.8 Phase diagram of H3PO4-H2O system[1]

图9 熔融结晶过程中的温度轨迹[65]

Fig.9 Temperature trajectories of melting crystallization[65]

图10 结晶和发汗过程溶质和杂质迁移的示意图[74]

Fig.10 Schematic diagram of solute and impurity migration during crystallization and sweating processes[74]

表7 悬浮熔融与层熔融结晶过程的差异［75］

Table 7 Difference between suspension melt crystallization and layer melt crystallization［75］

特征	悬浮熔融结晶	层熔融结晶
结晶温度	根据相图确定	根据相图确定
生长速率	10^-8~10^-7 m/s	10^-7~10^-5 m/s
结晶过程热传递	通过熔体	通过晶体层
晶体生长模式	晶体以颗粒状的形式生长	晶体以晶体层的形式粘贴在结晶器内壁
固液分离	难	易
转动装置	有	无

图11 降膜熔融结晶（FFMC）与静态熔融结晶（SMC）示意图[76]

Fig.11 Schematic diagram of the falling film and static melt crystallization[76]

图12 磷酸净化的静态层熔融结晶[32]

Fig.12 Static layer melting crystallization of phosphoric acid purification[32]

图13 悬浮结晶法制备电子级磷酸的流程图[84]

Fig.13 Flow chart of preparation of electronic grade phosphoric acid by suspension crystallization[84]

表8 磷酸的主要纯化精制方法对比

Table 8 Comparison of phosphoric acid purification techniques

技术	优点	缺点	文献
离子交换法	快速有效；对有些金属具有高选择性；低成本的材料和树脂可以再生	成本限制（初始和维护成本）；金属离子在树脂上结垢；对pH高度敏感	[33]
溶剂萃取法	处理简单，操作快速便捷	耗时、对环境不友好；产生副产品、工艺昂贵	[88]
沉淀法	设备简单；能选择性去除金属；沉淀剂相对便宜	硫化物量不可控；需要化学稳定的沉淀剂处理；需要大量沉淀剂，引入新的杂质；产生大量的杂质残渣	[89]
膜分离法	易于放大，操作简单；分离选择性高，压力低	运行成本高，使用寿命低；膜污染	[57-58]
冷却结晶法	一次性降低各种杂质离子含量；工艺流程短，投资费用低；操作控制要求不高	存在杂质包藏，需要多级结晶；考虑对母液的循环利用	[90]
熔融结晶法	能耗低；杂质去除率高	设备要求高；需要有特殊的结晶器	[91]

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