WO2018076902A1 - 晶棒的制作方法 - Google Patents
晶棒的制作方法 Download PDFInfo
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- WO2018076902A1 WO2018076902A1 PCT/CN2017/097849 CN2017097849W WO2018076902A1 WO 2018076902 A1 WO2018076902 A1 WO 2018076902A1 CN 2017097849 W CN2017097849 W CN 2017097849W WO 2018076902 A1 WO2018076902 A1 WO 2018076902A1
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B33/00—After-treatment of single crystals or homogeneous polycrystalline material with defined structure
- C30B33/02—Heat treatment
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/16—Oxides
- C30B29/20—Aluminium oxides
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/36—Carbides
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- C—CHEMISTRY; METALLURGY
- C30—CRYSTAL GROWTH
- C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
- C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
- C30B29/10—Inorganic compounds or compositions
- C30B29/40—AIIIBV compounds wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi
- C30B29/42—Gallium arsenide
Definitions
- the invention relates to a method for manufacturing an ingot, in particular to an annealing process for an ingot.
- Sapphire ( ⁇ -Al 2 O 3 ) crystal has excellent properties such as high hardness, high melting point, good light permeability, good thermal stability and chemical stability. It is widely used in national defense, aerospace, industrial and life fields, especially It is suitable as a substrate material for LED (Light Emitting Diode).
- LED Light Emitting Diode
- sapphire substrates account for more than 95% of semiconductor illumination substrates.
- the quality of the sapphire substrate (referred to as the substrate substrate) has a great influence on the growth of the subsequent GaN epitaxial layer and the performance and yield of the blue diode. The production of high quality LED products must first ensure the substrate substrate. quality.
- the sapphire ingot is a crystalline material for the substrate of the LED substrate, and the demand is enormous.
- Industrial sapphire single crystal growth methods include the Kyropoulos Method, the heat exchange method (HEM method), and the guided mold method (EFG), and the sapphire crystal rods produced by different companies and the same company.
- Different batches of sapphire crystal rods differ in the process of crystal growth and crucible rods, which makes the material and internal residual stress of different sapphire crystal rods have obvious differences, resulting in the consistency of sapphire wafers after the same process line cutting.
- CN102560631A discloses a more common sapphire annealing, which is carried out in the process of crystal growth.
- sapphire has not been subjected to the crowbar process, and the sapphire annealing is uneven due to the lack of uniform shape, and the design focus is different and the degree of vacuum is considered. It is required that most of the crystal growth furnaces do not have the function of precise annealing.
- the crowbar process after the crystal growth uses a tungsten steel barrel knife to quickly remove the ingot from the entire crystal, and the crowbar process also produces internal residual stress of different sizes.
- annealing is performed after the wafer is diced, although the warpage and stress are released to some extent, but since the wafer has been separated from the ingot, the annealing effect is not good and cannot be satisfied. Wafer consistency requirements. Taken together, the prior art does not achieve the desired results.
- the object of the present invention is to overcome the deficiencies of the prior art, and to provide a method for preparing an ingot, which is annealed at a high temperature, a long temperature, and an abrupt temperature to achieve different crystal growth and crowbar processes.
- the quality of the ingot is improved, the residual stress is eliminated, the consistency of the material of the ingot is improved, and the epitaxial yield and control rate of the LED are improved.
- the technical solution adopted by the present invention to solve the above technical problem is to provide an annealing process for an ingot, which does not limit the manufacturing process of the crystal, after the chopping process of the crystal and before the cutting of the ingot,
- the ingot is placed in a high temperature annealing furnace for annealing, and the annealing process mainly includes: a heating process, a constant temperature process, and a cooling process.
- the heating process is uniform temperature rise, and when the set maximum temperature is reached, the constant temperature process is entered, and the more the crystal rods are heated during the heating process, the slower the heating rate is required; the constant temperature process keeps the set temperature substantially constant and continues. Setting a time, and then entering a cooling process; the cooling process includes a rapid cooling process and a natural cooling process, wherein the rapid cooling process is to cool down according to a set cooling rate, the natural cooling process is to expose the ingot to room temperature air Naturally cooled.
- the maximum temperature reached by the heating process is 1700-1850 °C.
- the temperature increase rate of the temperature rising process is 50 to 200 ° C / h.
- the temperature rise temperature of the temperature rising process is 100 to 200 ° C / h.
- the constant temperature of the constant temperature process is 3 to 32 h.
- the constant temperature time is 22 to 32 hours.
- the rapid cooling process comprises two segments, and the first segment cooling speed is not greater than the second segment cooling velocity.
- the first stage is rapidly cooled and cooled to 1150 ° C to 1250 ° C, and the cooling rate is 150 ° C / h to 200 ° C / h; the second stage is rapidly cooled and cooled to 350 ° C to 450 ° C, and the cooling rate is 50 ° C / h ⁇ 100 ° C / h.
- the cooling process is converted to natural cooling when the temperature drops to between 350 ° C and 450 ° C.
- the method is also suitable for slicing processes of other crystalline materials such as silicon carbide, gallium arsenide, etc.; for different crystal materials A more suitable annealing temperature can be selected.
- the conformal consistency of the wafer (substrate) after processing will also be improved, that is, the warpage (BOW/WARP value) will be more concentrated.
- the warpage degree during epitaxial growth will be more concentrated, which is beneficial to the plating layer, the epitaxial control rate, and the yield improvement;
- segment annealing, the annealing time is controlled within the optimal range, to avoid unnecessarily prolonging the production cycle of the ingot, and at the same time different cooling speeds achieve the lowest cost to achieve the desired effect;
- the annealing conditions are relatively simple, which is conducive to popularization and application.
- the annealing process of the sapphire ingot of the present invention includes, but is not limited to, the embodiment.
- FIG. 1 Schematic diagram of the process flow of the present invention
- Figure 2 Trend graph of temperature versus time during the annealing process
- Figure 5 W2W std by circle bitmap (standard deviation of the circle wavelength between the slices);
- Figure 8 Schematic diagram of the appearance of the ingot after annealing.
- the figure shows: 1, crystal; 2, crystal rod; 3, wafer.
- a method for fabricating a sapphire ingot according to the present invention specifically includes the following steps:
- Step 1 the crystal growth method (Kyropoulos Method), heat exchange method (HEM method), and guided mold method (EFG) may be used for the growth of the crystal.
- the crystal growth method Kerropoulos Method
- HEM method heat exchange method
- ESG guided mold method
- This embodiment is preferably a bubble generation method, which is divided into a stage of seeding, shouldering, growth, and cooling, and the growth temperature and the heat flow field change of each stage are different, and the internal residual stress is also different; especially different.
- the size of the crystal 1 shortens the growth period in order to reduce the cost, as long as the crystal 1 is not cracked due to excessive stress, and the process time is shortened as much as possible. The difference in internal residual stress.
- the crystal 1 was taken out from the crystal growth furnace.
- the ingot 2 was quickly removed from the entire crystal 1 using a tungsten steel barrel knife.
- Step 2 10 10 inch crystal rods are placed in a high temperature annealing furnace for annealing process. It should be noted that 10 ingots are not limited to the same crystal growth and crowbar process, and have strong inclusiveness.
- the annealing process includes a heating process, a constant temperature process, and a cooling process.
- the heating process the highest temperature set in the heating process is 1700 ° C ⁇ 1850 ° C, this embodiment is preferably 1800 ° C, the crystal density in the temperature range after annealing reaches a better value, if the temperature is lower than the range value, the alumina atom can not be fully completed Rearrangement results in poor annealing.
- the temperature rise process uses uniform temperature rise to ensure that the crystal rod 2 does not crack due to excessive difference between the surface of the crystal rod and the center temperature during the heating process, especially when the larger the size and the number of the crystal rods 2 in the furnace chamber are, the temperature variation will occur. bigger. If the temperature rises too fast, it will cause stress, but it will have the opposite effect.
- the heating rate is generally recommended to be in the range of 100 ° C / h ⁇ 200 ° C / h, if the cavity is large, there are many ingots 2, it is recommended to raise the temperature of 50 ° C per hour to ensure the uniformity of the thermal field. Therefore, the temperature increase rate is set to 50 ° C / h to 200 ° C / h.
- Constant temperature process the temperature rise process reaches the set maximum temperature and enters the constant temperature process.
- the duration of the process is 3 ⁇ 32h, and the better duration is 22h ⁇ 32h.
- the constant temperature is 24h, see Figure 3 ⁇ 7, Compared with the existing sapphire ingot process, the annealing process after 24h constant temperature process and the annealing process after 30h constant temperature process. It can be seen from Fig. 3 and Fig. 4 that the distribution density (ordinate) of WARP/BOW after the constant temperature of 24h is the largest, that is, the distribution is concentrated, and on average, WARP/BOW (abscissa) is also the smallest, which significantly reduces the warpage value. And the distribution is more concentrated.
- the conventional wafer 3 has a significant difference in the performance of the inner and outer rings of the wafer 3 due to the warpage problem, and as can be seen from Fig. 5, the standard of the middle and outer ring curvature between the wafers 3 after the constant temperature of 24 hours.
- the difference is minimal, the wafer stability is good, the wavelength of the luminescent epitaxial layer is better, and the wavelength of the sheet and the sheet is more concentrated.
- the outer ring is generally not uniform, the method of the invention can be greatly improved, the wavelength is better controlled and adjusted; at the same time, the warpage after epitaxy is more concentrated, and the chip back grinding fragment can be reduced. Rate, improve chip processing yield.
- the wafer 3 of the 24h constant temperature process will be more concentrated than the existing process and the 30h constant temperature process.
- the uniformity of the K value of the subsequent package lamp is also greatly improved, and the K value of the wafer 3 fluctuates in a relatively small range.
- the sapphire wafer 3 produced by the preparation method for sapphire ingots of the present invention is used as an LED substrate, and the K value of the final package lamp is compared after the process of epitaxy and chip. Convergence and concentration can greatly reduce chip binning work and improve the quality of LED lights.
- Annealing process After a long period of constant temperature, the atoms are rearranged and then fixed by rapid cooling. The annealing process is naturally cooled after rapid cooling. The rapid cooling is cooled according to the set temperature, and the rapid cooling is divided into two sections. The first section of the rapid cooling and cooling rate is greater than the second section of the cooling rate. The purpose is to quickly fix the atomic state in the active phase of the high temperature atom to achieve the purpose of eliminating stress concentration.
- a cooling rate of 150 ° C / h ⁇ 200 ° C / h the temperature is reduced to 1150 ° C ⁇ 1250 ° C, this embodiment is preferably 1200 ° C; the second stage cooling rate is 50 ° C / h ⁇ 100 ° C / h, the first The second stage of cooling does not need to consume a large amount of energy to maintain the rapid cooling rate and reduce the production cost.
- the temperature is preferably 80 ° C / h, the temperature is lowered to 350 ⁇ 450 ° C, this embodiment is preferably 400 ° C; 2 Exposure to room temperature air for cooling further reduces costs.
- a comparison of the annealing process for the sapphire ingot 2 of the present invention is performed before and after annealing. After annealing, due to the high temperature holding time, the atom is rearranged and then fixed by rapid cooling. In addition to the ashing phenomenon of baking the surface impurities, a more transparent thermal polishing phenomenon (Thermal polish) is also exhibited.
- Step 3 Wire cutting the sapphire ingot 2 to form a sapphire wafer 3, which can be on the sapphire wafer 3 A light emitting semiconductor epitaxial layer material is grown thereon.
- the invention also provides a manufacturing method for fabricating the wafer 3 of the silicon carbide crystal 1, solving the problem of warpage of the silicon carbide wafer 3, step one, growing the silicon carbide crystal 1, and not limiting the growth process of the silicon carbide crystal 1, in the silicon carbide
- the silicon carbide ingot 2 is annealed. Since the silicon carbide is decomposed at around 1850 ° C, the highest temperature during the temperature rise of the silicon carbide ingot 2 is compared to that in the first embodiment. Set to 1700 ° C ⁇ 1800 ° C. The temperature rise process maintains a uniform temperature increase rate, and the temperature increase rate is 50 ° C to 200 ° C.
- the rapid cooling rate is 50 ° C ⁇ 200 ° C.
- the temperature is cooled to 350 ⁇ 450 ° C, it enters natural cooling.
- the ingot 2 is cut, and the cut wafer 3 is used for other processes.
- the material of the ingot is gallium arsenide. Since the melting point of gallium arsenide is lower than that of silicon carbide and the melting point is 1238 ° C, the maximum temperature of the temperature rising process is set to 900 ° C to 1150 ° C. It is preferably 900 ° C to 1050 ° C, and its temperature rising rate, constant temperature process and rapid cooling process are similar to silicon carbide crystals.
- the ingot can also be made using the method of the present invention.
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Abstract
一种晶棒的制作方法,在线切割前将已完成掏棒工艺的晶棒放入高温退火炉中进行退火,其退火工艺过程主要包括:升温过程、恒温过程、降温过程,通过对不同长晶和掏棒工艺下生产的晶棒进行统一退火处理,消除晶棒内部残余应力,提高蓝宝石晶棒材质的一致性,提高后段晶圆加工、外延的良率和均匀性。
Description
本发明涉及一种晶棒的制作方法,尤其涉及一种用于晶棒的退火工艺方法。
蓝宝石(α-Al2O3)晶体具有硬度高、熔点高、光透性好、热稳定性好和化学性质稳定等优良特性,在国防、航空航天、工业以及生活领域中得到广泛应用,特别适合作为LED(Light Emitting Diode)的衬底材料。目前,蓝宝石衬底占半导体照明衬底的95%以上。蓝宝石衬底基片(简称衬底基片)的质量对后续GaN外延层的生长以及制备蓝光二极管的性能和成品率有很大的影响,高品质LED产品的生产首先要保证衬底基片的质量。
蓝宝石晶棒作为制作LED衬底基片的晶体材料,需求量极大。工业用蓝宝石单晶的生长方法包括泡生法(Kyropoulos Method)、热交换法(HEM法)、导模法(EFG)等三大类型,而由于不同公司生产的蓝宝石晶棒以及同一公司生产的不同批次的蓝宝石晶棒在长晶、掏棒工艺上有所不同,使得不同的蓝宝石晶棒的材质、内部残余应力存在明显的差异,从而导致采用相同工艺线切后的蓝宝石晶片的一致性较差(例如:Bow、Warp、TTV等参数之间存在很大差异),影响后续的平片加工的质量,且会造成后续外延到芯片所补正的K值(一致性参数)的波动大,因为晶棒厂家不同而有所不同,造成生产管理上的不便。
例如CN102560631A公开了一种较常见的蓝宝石退火,退火在长晶过程中进行,然而蓝宝石尚未进行掏棒工艺,由于没有均匀的形状导致蓝宝石退火不均匀,又由于设计侧重点不同以及考虑到真空度要求,实际上绝大多数的长晶炉也不具备精确退火的功能。除此之外,长晶之后的掏棒工艺用钨钢桶刀快速地将晶棒从整个晶体钻取出来,掏棒过程也会产生不同大小的内部残余应力。
又例如,现有技术也有在切割晶圆后进行退火,虽然能一定程度上改善翘曲度,释放应力,然而由于晶圆已经从晶棒上分离,此时退火效果不佳,无法满足
晶圆的一致性要求。综合来看,现有技术无法达到理想的效果。
本发明的目的在于克服现有技术之不足,提供了一种用于晶棒的制备工艺方法,将晶棒以高温、长持温、急降温的退火,实现了不同晶体生长、掏棒工艺下的晶棒的质量提升,消除残余应力,提高晶棒材质的一致性,进而提高LED外延良率与控制率。
问题的解决方案
本发明解决上述技术问题所采用的技术方案是:提供一种用于晶棒的退火工艺方法,本方法不限定晶体的制作工艺,在对晶体的掏棒工艺之后、对晶棒进行切割之前,将晶棒放入高温退火炉中进行退火,其退火工艺过程主要包括:升温过程、恒温过程、降温过程。
所述升温过程为均匀升温,当达到设置的最高温度后,进入恒温过程,所述升温过程中晶棒越多,升温速度需要越慢;所述恒温过程即保持所设置温度基本不变并持续设定时间,然后进入降温过程;所述降温过程包括快速冷却过程和自然冷却过程,所述快速冷却过程为按照设定降温速度进行降温,所述自然冷却过程即将晶棒暴露于室温空气中进行自然冷却。
优选的,所述升温过程达到的最高温度为1700~1850℃。
优选的,所述升温过程的升温速度为50~200℃/h。
优选的,所述升温过程的升温温度为100~200℃/h。
优选的,所述恒温过程的恒温时间为3~32h。
优选的,所述恒温时间为22~32h。
优选的,所述快速冷却过程包括两段,第一段降温速度不大于第二段降温速度。
优选的,第一段快速冷却降温至1150℃~1250℃,降温速度为150℃/h~200℃/h;第二段快速冷却降温至350℃~450℃,降温速度为50℃/h~100℃/h。
优选的,所述降温过程在温度下降到350℃~450℃之间,转换成自然冷却。
该方法也适合碳化硅、砷化镓等其他晶体材料的切片工艺;针对不同的晶体材
料可以选用更合适的退火温度。
发明的有益效果
本发明的有益效果是:
1、实现了针对不同长晶、掏棒工艺下的蓝宝石晶棒的退火处理,消除残余应力,提高蓝宝石晶棒材质的一致性;
2、因为退火后内应力一致性高,晶圆(衬底)加工后的形貌一致性也会提高,即翘曲度(BOW/WARP值)会更集中。此外,在PVD(物理气相沉积)镀层、外延生长时的翘曲度也会更集中,有利于镀层、外延控制率、良率的提升;
3、改善了晶棒切割成晶圆后的品质问题,在晶棒加工的末段先做更高温度的退火,可改善晶圆切割、研磨时的崩角(chipping)不良率1~3%;
4、分段退火,将退火时间控制在最优的范围,避免不必要地延长晶棒的制作周期,同时不同的降温速度实现最低成本达到所要效果的目的;
5、退火条件相对简单,有利于推广应用。
以下结合附图及实施例对本发明作进一步详细说明;但本发明的蓝宝石晶棒的退火工艺方法包括但不局限于实施例。
对附图的简要说明
图1:本发明工艺流程示意图;
图2:退火工艺中温度随时间变化的趋势图;
图3:不同持续时间WARP(翘曲)分布图;
图4:不同持续时间BOW(弯曲)分布图;
图5:W2W std by圈位图(片与片之间的圈位波长标准差);
图6:BOW发散图;
图7:包灯K值对比图;
图8:退火后晶棒外观示意图。
图中标识:1、晶体;2、晶棒;3、晶圆。
发明实施例
实施例1
参见图1所示,本发明的一种用于蓝宝石晶棒的制作方法,具体包括如下步骤:
步骤一:本实施例可以选用泡生法(Kyropoulos Method)、热交换法(HEM法)、导模法(EFG)等方式进行长晶。晶体生长过程中,由于生长速度的控制,需严格控制腔体内温度梯度的变化,且随著晶体的体积增加,内部温场的变化更为复杂。
本实施例优选为泡生法,分成引晶、放肩、生长、降温等阶段,每阶段的生长温度、热流场变化均有所不同,对于内部残留的应力大小也有所不同;尤其是不同尺寸的晶体1,为了降低成本而缩短生长周期,只要晶体1不因为应力过大导致开裂,尽可能地缩短制程时间。内部残留应力的不同。从长晶炉取出晶体1。
采用钨钢桶刀快速地将晶棒2从整个晶体1钻取出来。
步骤二:将10根4寸晶棒放置于高温退火炉中进行退火工艺,需要注意的是,10根晶棒并不限定于相同的长晶、掏棒工艺,具有很强的包容性。参看图2,其退火工艺依次包括:升温过程、恒温过程、降温过程。
升温过程:升温过程设置的最高温度为1700℃~1850℃,本实施例优选为1800℃,该温度范围内退火后晶体密度达到较佳值,如果温度低于范围值,氧化铝原子无法充分完成重新排列,导致退火效果不佳。升温过程采用均匀升温,确保晶棒2在升温过程中不会因为晶棒表面、中心温度差异过大而崩裂,尤其是越大尺寸、炉腔内的晶棒2数量多的时候,温度变异会比较大。如果过快的升温也会造成应力,反而起到相反的效果。升温速度一般建议在100℃/h~200℃/h,若是腔体很大,容纳的晶棒2很多,建议每小时50℃升温,确保热场均匀性好的状况下进行。所以升温速度设定为50℃/h~200℃/h。
恒温过程:升温过程达到设定的最高温度后进入恒温过程,该过程持续时间为3~32h,更佳的持续时间为22h~32h,本实施例采用24h恒温,参看图3~图7,对
比现有的蓝宝石晶棒制程、经过24h恒温过程的退火工艺和经过30h恒温过程的退火工艺。从图3和图4可以看出,经过24h恒温过程的WARP/BOW的分布密度(纵坐标)最大,即分布集中,平均来看WARP/BOW(横坐标)也最小,明显降低翘曲值,并且分布更集中。常规的晶圆3由于翘曲度问题导致晶圆3中圈和外圈性能差异明显,而从图5可以看出,经过24h恒温过程的晶圆3之间中圈和外圈弯曲度的标准差最小,晶圆稳定性好,发光外延层显示的波长均匀性更好,且片与片的波长更集中。尤其是大型外延机台,外圈通常均匀性不佳,本发明的方法可获得大幅的改善,波长更好控制和调整;同时外延后的翘区度也更为集中,可减少芯片背磨破片率,提升芯片加工良率。再看图6,24h恒温过程的晶圆3相对现有制程和30h恒温过程,BOW值会更加集中。从图7可以看出,对后续包灯K值均匀性也有很大改善,晶圆3的K值在比较小的范围波动。与目前量产的对比,经本发明的一种用于蓝宝石晶棒的制备工艺方法所生产的蓝宝石晶圆3作为LED衬底,经过外延、芯片的过程,到最后的包灯测试K值较为收敛、集中,可大幅减少芯片分档工作提高LED灯品质。
退火过程:经过长时间的恒温过程,原子重新排列后利用快速冷却将型态予以固定。退火过程在快速冷却之后进行自然冷却。快速冷却按设定温度降温,快速冷却分为两段进行,第一段快速冷却降温速度大于第二段降温速度,目的在高温原子活跃阶段,快速固定原子状态,实现消除应力集中的目的,第一段降温速度为150℃/h~200℃/h,将温度降低到1150℃~1250℃,本实施例优选为1200℃;第二段降温速度为50℃/h~100℃/h,第二段降温不需要消耗大量能源去维持快速降温速度,降低生产成本,本实施例优选为80℃/h,将温度降低到350~450℃,本实施例优选为400℃;自然冷却即将晶棒2暴露于室温空气中进行冷却,进一步降低成本。
参见图8所示,本发明的一种用于蓝宝石晶棒2的退火工艺方法的退火前后比较。退火后由于高温持温时间较长,原子重新排列后利用快速冷却将型态予以固定,除了将表面杂质烤干净的灰化现象,也会呈现较透明的热抛现象(Thermal polish)。
步骤三:对蓝宝石晶棒2进行线切割,形成蓝宝石晶圆3,可以在蓝宝石晶圆3
上生长发光半导体外延层材料。
本实施例,提出在线切割前对蓝宝石晶棒进行统一退火处理,以提高晶棒材质的均匀性,消除晶棒内部的残余应力,通过改善蓝宝石品质,提高蓝宝石晶圆的线切割质量,并使所切切割的晶圆具有较好的一致性,使得切割出的晶片一致性较好。也可以直接通过对不同长晶和掏棒工艺下生产的晶棒进行统一退火处理,消除晶棒内部参与应力,提高蓝宝石晶棒材质的一致性。每一片衬底的应力都接近的情况之下,进行PVD、外延制程的流场包括气体与温度流场,会比原本就应力不同的衬底来得均匀。所以更容易实现这些PVD或外延制程的控制,提高生产良率。
实施例2
本发明也为碳化硅晶体1制作晶圆3提供了制作方法,解决碳化硅晶圆3的翘曲问题,步骤一,生长碳化硅晶体1,不限定碳化硅晶体1的生长工艺,在碳化硅晶体1掏棒成晶棒后,对碳化硅晶棒2进行退火工艺,因为碳化硅在1850℃左右就会分解了,所以相比于实施例1,碳化硅晶棒2的升温过程中最高温度设定为1700℃~1800℃。升温过程保持均匀的升温速度,升温速度为50℃~200℃。在达到最高温度后进入恒温过程,恒温过程时间为3h~32h。恒温过程结束后开始快速冷却,快速冷却的速度为50℃~200℃,当温度冷却到350~450℃后,进入自然冷却。
退火后对晶棒2进行切割,切割后的晶圆3供其他工艺使用。
实施例3
本实施例与实施例2的区别在于晶棒的材料为砷化镓,由于砷化镓的熔点低于碳化硅,熔点为1238℃,所以升温过程的最高温度设定为900℃~1150℃,优选为900℃~1050℃,其升温速度、恒温过程和快速降温过程与碳化硅晶体近似。也可以利用本发明的方法制作晶棒。
上述实施例仅用来进一步说明本发明的一种晶棒的制作方法,但本发明并不局限于实施例,凡是依据本发明的技术实质对以上实施例所作的任何简单修改、等同变化与修饰,均落入本发明技术方案的保护范围内。
Claims (12)
- 一种晶棒的制作方法,包括步骤:(1)长晶后对晶体进行掏棒,得到晶棒;(2)对所述晶棒进行退火工艺,退火工艺依次包括:升温过程、恒温过程、降温过程。
- 根据权利要求1所述的一种晶棒的制作方法,其特征在于,所述升温过程采用均匀升温,恒温过程保持温度不变。
- 根据权利要求1所述的一种晶棒的制作方法,其特征在于,所述升温过程中晶棒越多,升温速度越慢。
- 根据权利要求1所述的一种晶棒的制作方法,其特征在于,所述升温速度为50℃/h~200℃/h。
- 根据权利要求1所述的一种晶棒的制作方法,其特征在于,所述晶棒的材料为碳化硅或砷化镓。
- 根据权利要求1所述的一种晶棒的制作方法,其特征在于,所述晶棒的材料为蓝宝石。
- 根据权利要求6所述的一种晶棒的制作方法,其特征在于,所述升温过程设置的最高温度为1700℃~1850℃。
- 根据权利要求6所述的一种晶棒的制作方法,其特征在于,所述恒温时间为3~32h。
- 根据权利要求6所述的一种晶棒的制作方法,其特征在于,所述恒温时间为22~32h。
- 根据权利要求6所述的一种晶棒的制作方法,其特征在于,所述降温过程至少分为快速冷却和自然冷却,在快速冷却之后进行自然冷却,所述自然冷却为将晶棒暴露于室温空气中进行冷却。
- 根据权利要求10所述的一种晶棒的制作方法,其特征在于,所述快速冷却为按设定降温速度冷却,所述快速冷却包括两段,第一段降温速度大于第二段降温速度。
- 根据权利要求11所述的一种蓝宝石晶棒的制作方法,其特征在于 ,第一段快速冷却降温至1150℃~1250℃,降温速度为150℃/h~200℃/h;第二段快速冷却降温至350℃~450℃,降温速度为50℃/h~100℃/h。
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Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110008621A1 (en) * | 2006-03-30 | 2011-01-13 | Schujman Sandra B | Aluminum nitride bulk crystals having high transparency to ultraviolet light and methods of forming them |
CN102560631A (zh) * | 2012-01-20 | 2012-07-11 | 上海中电振华晶体技术有限公司 | 蓝宝石晶体的生长方法及设备 |
CN102806609A (zh) * | 2012-08-15 | 2012-12-05 | 四川欣蓝光电科技有限公司 | 一种高效低成本的蓝宝石晶圆棒掏棒方法 |
CN103194802A (zh) * | 2012-01-05 | 2013-07-10 | 昆山中辰矽晶有限公司 | 晶棒表面之调质方法及其晶棒 |
CN104088014A (zh) * | 2014-07-11 | 2014-10-08 | 江苏中电振华晶体技术有限公司 | 一种棒状蓝宝石晶体生长设备及其生长方法 |
US9444216B2 (en) * | 2010-08-27 | 2016-09-13 | National Taiwan University | Method of manufacturing a Ti:sapphire crystal fiber by laser-heated pedestal growth |
CN106544738A (zh) * | 2016-10-31 | 2017-03-29 | 福建晶安光电有限公司 | 一种晶棒的制作方法 |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103014874A (zh) * | 2013-01-11 | 2013-04-03 | 焦作市光源晶电科技有限公司 | 一种蓝宝石晶体退火工艺 |
CN103540998A (zh) * | 2013-08-20 | 2014-01-29 | 曾锡强 | 一种泡生法生长大尺寸蓝宝石晶体的退火工艺 |
CN103643300B (zh) * | 2013-11-26 | 2017-04-12 | 浙江上城科技有限公司 | 一种用于蓝宝石加工过程中的退火方法 |
CN105332060A (zh) * | 2015-10-30 | 2016-02-17 | 江苏吉星新材料有限公司 | 蓝宝石晶片的二次退火方法 |
-
2016
- 2016-10-31 CN CN201610928820.6A patent/CN106544738B/zh active Active
-
2017
- 2017-08-17 WO PCT/CN2017/097849 patent/WO2018076902A1/zh active Application Filing
-
2019
- 2019-04-30 US US16/398,732 patent/US20190264349A1/en not_active Abandoned
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110008621A1 (en) * | 2006-03-30 | 2011-01-13 | Schujman Sandra B | Aluminum nitride bulk crystals having high transparency to ultraviolet light and methods of forming them |
US9444216B2 (en) * | 2010-08-27 | 2016-09-13 | National Taiwan University | Method of manufacturing a Ti:sapphire crystal fiber by laser-heated pedestal growth |
CN103194802A (zh) * | 2012-01-05 | 2013-07-10 | 昆山中辰矽晶有限公司 | 晶棒表面之调质方法及其晶棒 |
CN102560631A (zh) * | 2012-01-20 | 2012-07-11 | 上海中电振华晶体技术有限公司 | 蓝宝石晶体的生长方法及设备 |
CN102806609A (zh) * | 2012-08-15 | 2012-12-05 | 四川欣蓝光电科技有限公司 | 一种高效低成本的蓝宝石晶圆棒掏棒方法 |
CN104088014A (zh) * | 2014-07-11 | 2014-10-08 | 江苏中电振华晶体技术有限公司 | 一种棒状蓝宝石晶体生长设备及其生长方法 |
CN106544738A (zh) * | 2016-10-31 | 2017-03-29 | 福建晶安光电有限公司 | 一种晶棒的制作方法 |
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