镀膜技术十个主要问题及答案Coating technology ten main problems and solutions
问题：questions
一、 镀膜技术可区分为哪几类? what kinds of coating technology can be distinguished into?
可区分为：(1)真空蒸镀 (2)电镀 (3)化学反应 (4)热处理 (5)物理或机械处理
(1) vacuum evaporation (2) electroplating (3) chemical reaction (4) heat treatment (5) physical or mechanical treatment二、 常用的真真空泵浦有哪几种? 适用的抽气范围如何? What are the types of vacuum pumps? What is the applicable exhaust range?
真空泵浦可分：
(1)机械帮浦 (2)扩散泵浦 (3)涡轮泵浦 (4)吸附泵浦 (5)吸着泵浦
(1) mechanical pump (2) diffusion pump (3) turbo pump (4) adsorption pump (5) suction pump真空泵浦抽气范围：
泵 浦 抽 气 范 围 Pumping and pumping limits
机 械 泵 浦 10-1 ~ 10-4 毫巴
扩 散 泵 浦 10-3 ~ 10-6 毫巴
涡 轮 泵 浦 10-3 ~ 10-9 毫巴
吸 附 泵 浦 10-3 ~ 10-4 毫巴
吸 着 泵 浦 10-4 ~ 10-10 毫巴
Mechanical pump 10-1 ~ 10-4 mbar
Dispersion pump 10-3 ~ 10-6 mbar
Turbo pump 10-3 ~ 10-9 mbar
Suction pump 10-3 ~ 10-4 mbar
Suction pump 10-4 ~ 10-10 mbar
三.电浆技术在表面技术上的应用有哪些?What are the applications of plasma technology in surface technology?
1)溅浆沉积：溅镀是利用高速的离子撞击固体靶材，使表面分子溅离并射到基材镀成一层薄膜，溅射离子的起始动能约在100eV。常用的电浆气体为氩气，质量适当而且没有化学反应。
Sputtering deposition: sputtering is the use of high speed ions hitting solid target, causing the surface molecules to spatter and shoot into the substrate to be plated into a thin film. The initial kinetic energy of sputtering ions is about 100eV. The commonly used plasma gas is argon, which is of proper quality and has no chemical reaction.
(2)电浆辅助化沉积：气相化学沉积的化学反应是在高温基材上进行，如此才能使气体前置物获得足够的能量反应。
Plasmone-assisted deposition: chemical reactions in vapor deposition occur on a high-temperature substrate so that the gas precursors can react with sufficient energy.
(3)电浆聚合：聚合物或塑料薄膜最简单的披覆技术就是将其溶剂中，然后涂布于基板上。电浆聚合涂布法系将分子单体激发成电浆，经化学反应后形成一致密的聚合体并披覆在基板上，由于基材受到电浆的撞击，其附着性也很强。
Plasma polymerization: the simplest coating technique for a polymer or plastic film is to put it in a solvent and then apply it to a substrate. The coating system of plasma polymerization excites monomer molecules into plasma, and after chemical reaction, a dense polymer is formed and coated on the substrate. As the substrate is hit by plasma, its adhesion is also very strong.
(4)电浆蚀刻：湿式碱性蚀刻，这是最简单而且便宜的方法，它的缺点是碱性蚀刻具晶面方向性，而且会产生下蚀的问题。
Plasma etching: wet alkaline etching, which is the simplest and least expensive method, has the disadvantage that alkaline etching has the orientation of the crystal plane and can lead to erosion problems.
(5)电浆喷覆：在高温下运转的金属组件须要有陶瓷物披覆，以防止高温腐蚀的发生。
Plasma coating: ceramic coating is required for metal components operating at high temperature to prevent corrosion at high temperature.
四、 蒸镀的加热方式包括哪几种?各具有何特点?
What are the heating methods of evaporation? What are their characteristics?
加热方式分为：(1)电阻加热 (2)感应加热 (3)电子束加热 (4)雷射加热 (5)电弧加热。
Heating methods are divided into :(1) resistance heating (2) induction heating (3) electron beam heating (4) laser heating (5) arc heating.
各具有的特点：Each has its own characteristics:
(1)电阻加热：这是一种最简单的加热方法，设备便宜、操作容易是其优点。
resistance heating: this is one of the simplest heating methods, with the advantages of cheap equipment and easy operation.
(2)感应加热：加热效率佳，升温快速，并可加热大容量。
induction heating: good heating efficiency, fast heating, and large capacity heating.
(3)电子束加热：这种加热方法是把数千eV之高能量电子，经磁场聚焦，直接撞击蒸发物加热，温度可以高达30000C。而它的电子的来源有二：高温金属产生的热电子，另一种电子的来源为中空阴极放电。
Electron beam heating: this is done by focusing thousands of eV of high-energy electrons through a magnetic field and directly hitting the vaporizer. The temperature can reach up to 30000C. And its electron source has two: the hot electron that high temperature metal produces, another kind of electron source is hollow cathode discharge.
(4)雷射加热：激光束可经由光学聚焦在蒸镀源上，产生局部瞬间高温使其逃离。最早使用的是脉冲红宝雷射，而后发展出紫外线准分子雷射。紫外线的优点是每一光子的能量远比红外线高，因此准分子雷射的功率密度甚高，用以加热蒸镀的功能和电子束类似。常被用来披覆成份复杂的化合物，镀膜的品质甚佳。它和电子束加热或溅射的过程有基本上的差异，准分子雷射脱离的是微细的颗粒，后者则是以分子形式脱离。
Laser heating: the laser beam can be optically focused on the evaporation source, producing local instantaneous high temperature to make it escape. The first use was the pulsed red laser, and then the uv excimer laser was developed. The advantage of uv is that the energy per photon is much higher than that of infrared, so excimer lasers have a high power density that ACTS like electron beams to heat and evaporate. It is often used to coat complex compounds, and the coating quality is very good. It is fundamentally different from the process of electron beam heating or sputtering, in which excimer lasers break away from fine particles, which break away as molecules.
(5)电弧加热：阴极电弧沉积的优点为：Arc heating: advantages of cathode arc deposition:
a、蒸镀速率快，可达每秒1.0微米Evaporation rate is fast, up to 1.0 micron per second
b、基板不须加热The substrate does not need to be heated
c、可镀高温金属及陶瓷化合物High temperature metal and ceramic compounds can be plated
d、镀膜密高且附着力佳Coating high density and good adhesion
五、真空蒸镀可应用在哪些产业？What industries can vacuum evaporation be used in
主要产业大多应用于装饰、光学、电性、机械及防蚀方面等，现就比较常见者分述如下：
The main industries are mostly used in decoration, optics, electrical, mechanical and corrosion prevention, etc., which are described as follows:
(1)镜片的抗反射镀膜(MgO、MgF2、SiO2等)，镜片置于半球支顶，一次可镀上百片以上。
anti-reflection coating of the lens (MgO, MgF2, SiO2, etc.), with the lens placed on the top of the hemispheric branch, can be plated over 100 pieces at a time.
(2)金属、合金或化合物镀膜，应用于微电子当导线、电阻、光电功能等用途。 _
metal, alloy or compound coating, used for microelectronics as wires, resistors, photoelectric functions, etc. _
(3)镀铝或钽于绝缘物当电容之电极。
electrode of aluminized or tantalum used as capacitor in insulation.
(4)特殊合金镀膜MCrAlY具有耐热性抗氧化性，耐温达1100OC，可应用须耐高温环境的工件，如高速切削及成形加工、涡轮引擎叶片等。
MCrAlY coated with special alloy has heat resistance and oxidation resistance up to 1100OC, which can be applied to workpiece with high temperature resistance, such as high-speed cutting and forming, turbine engine blade, etc.
(5)镀金属于玻璃板供建筑物之装饰及防紫外线。
gold plating belongs to glass panels for building decoration and uv protection.
(6)离子蒸镀镀铝，系以负高电压加在被镀件上，再把铝加热蒸发，其蒸气经由电子撞击离子化，然后镀到钢板上。
ion evaporation, which is applied at a negative high voltage to the plated part, is then heated and evaporated. The vapor is ionized by electron impact and then plated on the steel plate.
(7)镀铝于胶膜，可供装饰或标签，且镀膜具有金属感等。最大的用途就是包装，可以防潮、防空气等的渗入。
aluminized in the film, for decoration or label, and the film has a metal sense. The biggest use is packing, can moistureproof, prevent the infiltration of air and so on.
(8)机械零件或刀磨具镀硬膜(TiC、TiN、Al2O3)这些超硬薄膜不但硬度高，可有效提高耐磨性，而且所需厚度剪小，能符合工件高精度化的要求。
mechanical parts or knife grinding tools plated dura (TiC, TiN, Al2O3) these super hard film not only hardness is high, can effectively improve the wear resistance, and the required thickness is small, can meet the requirements of high precision workpiece.
(9)特殊合金薄片之制造。
manufacture of special alloy sheet.
(10)镀多层膜于钢板，改善其性能。
multilayer coating on steel plate to improve its performance.
(11)镀硅于CdS太阳电池，可增加其效率。
silicon plating on CdS solar cells can increase their efficiency.
(12)奈米粉末之制造，镀于冷基板上，使其不附着。
manufacture of nano-powder, plated on a cold substrate so that it does not adhere.
六、TiN氮化钛镀膜具有哪些特点?What are the characteristics of TiN titanium nitride coating
有以下的优点：It has the following advantages:
(1)抗磨损resistance to wear
(2)具亮丽的外观with bright appearance
(3)具安全性，可使用于外科及食品用具。safe for use in surgery and food utensils.
(4)具润滑作用，可减少磨擦。with lubrication, can reduce friction.
(5)具防蚀功能with anti-corrosion function
(6)可承受高温 can withstand high temperature
七、CVD化学气相沉积法反应步骤可区分为哪五个步骤？
What are the five steps of CVD chemical vapor deposition?
(1)不同成份气相前置反应物由主流气体进来，以扩散机制传输基板表面。理想状况下，前置物在基板上的浓度是零，亦即在基板上立刻反应，实际上并非如此。
the prereactants in the gas phase of different components come in from the mainstream gas to transfer the substrate surface by diffusion mechanism. Ideally, the concentration of the precursors on the substrate would be zero, which means that they react immediately on the substrate, which is not the case.
(2)前置反应物吸附在基板上，此时仍容许该前置物在基板上进行有限程度的表面横向移动。
the pre-reactant is adsorbed on the substrate, and the pre-reactant is still allowed to conduct a limited degree of lateral surface movement on the substrate.(3)前置物在基板上进行化学反应，产生沉积物的化学分子，然后经积聚成核、迁移、成长等步骤，最后联合一连续的膜。
the precursors undergo chemical reactions on the substrate to produce chemical molecules in the sediments, which then undergo the steps of accumulation, nucleation, migration, growth, and finally combine with a continuous membrane.
(4)把多余的前置物以及未成核的气体生成物去吸附。
adsorption of excess precursors and unnucleated gas products.
(5)被去吸附的气体，以扩散机制传输到主流气相，并经传送排出。
the desorbed gas is transferred to the mainstream gas phase by the diffusion mechanism, and is then transported out.
八、电浆辅助VCD系统具有何特色?
What are the features of plasma - assisted VCD system?
一般CVD均是在高温的基板下产生沉积反应，如果以电浆激发气体，即所谓的电浆辅助CVD(Plasma enhanced CVD 简称PECVD)，则基板温度可以大幅降低。然而一般薄层的光电镀膜或次微米线条，相当脆弱，容易受到电浆离子撞击的伤害，故PECVD并不适宜。
Generally, CVD generates deposition reaction under a high-temperature substrate. If Plasma excites the gas, known as Plasma enhanced CVD(PECVD), the substrate temperature can be significantly reduced. However, generally thin layers of photoelectric coating or submicron lines are quite fragile and vulnerable to plasma ion impact, so PECVD is not appropriate.
九、CVD制程具有哪些优缺点?
What are the advantages and disadvantages of CVD process?
优点advantages ：
(1)真空度要求不高，甚至不须真空，如热喷覆。
the vacuum requirement is not high, even without vacuum, such as hot spray.
(2)高沉积速率，APCVD可以达到1μm/min。
with a high deposition rate, APCVD can reach 1μm/min.
(3)相对于PVD，化学量论组成或合金的镀膜比较容易达成。
compared with PVD, the coating of chemical components or alloys is easier to achieve.
(4)镀膜的成份多样化，包括金属、非金属、氧化物、氮化物、碳化物、半导体、光电材料、聚合物以及钻石薄膜等。
the coating has various components, including metal, nonmetal, oxide, nitride, carbide, semiconductor, photoelectric material, polymer and diamond film.
(5)可以在复杂形状的基材镀膜，甚至渗入多孔的陶瓷。
can be in the complex shape of the substrate coating, and even infiltration of porous ceramics.
(6)厚度的均匀性良好， LPCVD甚至可同时镀数十芯片。
the thickness uniformity is good, and LPCVD can even be plated with dozens of chips at the same time.
缺点disadvantages ：
(1)热力学及化学反应机制不易了解或不甚了解。
thermodynamics and chemical reaction mechanism are not easy or well understood.
(2)须在高温度下进行，有些基材不能承受，甚至和镀膜起作用。
must be carried out in high temperature, some base material can not bear, and even coating effect.
(3)反应气体可能具腐蚀性、毒性或爆炸性，处理需格外小心。
the reaction gas may be corrosive, toxic or explosive, so extra care should be taken.
(4)反应生成物可能残余在镀膜，成为杂质。
the reaction products may remain in the coating and become impurities.
(5)基材的遮蔽很难。
it is difficult to cover the base material.
十、钻石材料具有那些优点?可应用在哪些产业上?
What are the advantages of diamond materials? What industries can it be applied to?
优点：硬度高、耐磨性高、低热胀率、散热能力良好、防蚀能力加等等。
Advantages: high hardness, high wear resistance, low thermal expansion rate, good heat dissipation ability, corrosion resistance and so on.
可应用在：声学产品、消费产品、生医产品、光学产品、超级磨料、航天产品、钻石制造、化学产品、电子产品、机械产品。
Applications: acoustic products, consumer products, biomedical products, optical products, super abrasives, aerospace products, diamond manufacturing, chemical products, electronic products, mechanical products.
十一、钻石薄膜通常可使用哪些方法来获得?
What methods can be used to obtain diamond film?
近年来膜状的钻石合成技术突飞猛进。钻石膜的厚度，可自奈米至毫米。薄膜常以物理气相沉积的方法生成。厚膜则多以化学气相沉积的方法获得。
In recent years, membrane diamond synthesis technology has advanced by leaps and bounds. Diamond film thickness, from nanometer to mm. Thin films are often formed by physical vapor deposition. Thick films are usually obtained by chemical vapor deposition.
十二、试说明PVD法生长钻石薄膜之特性?
Explain the properties of diamond film grown by PVD method.
PVD沉积钻石时除撞击区的少数原子外，其它的碳原子乃在真空下，而且温度很低，因此常被认为是低压法。由于钻石在低压为介稳定状态故PVD法乃被归类为介稳定生长钻石的方法。但在生长钻石的撞击区碳原子所受的压力及温度都很高。由于高温影响的区域有限，因此钻石乃在非平衡状态下长出。在这种情况原子不易扩散，生出钻石的原子排列只是短程有序，但长程排列则含极多缺陷，甚至也含大量杂质，故称为类钻碳。以PVD法生长钻石或DLC因基材温度很低，生长速率缓慢，通常只沉积极薄的一层。由于膜较薄，可附在复杂的工件表面上。镀DLC膜时因工件不受高温影响，所以PVD沉积的DLC用途广泛，可用为模具涂层及硬盘护膜等。若要生长较厚的钻石膜，原子必须扩散至晶格内的稳定位置，因此基材温度要提高，但也不能高到使生出的钻石转化成石墨。
When PVD deposits a diamond, except for a few atoms in the impact zone, the other carbon atoms are in a vacuum and at very low temperatures, so it is often considered a low pressure method. Because diamonds are in the medium stable state at low pressure, PVD method is classified as medium stable diamond growth method. But the pressure and temperature on the carbon atoms in the impact zone where diamonds grow are high. Because the area affected by high temperatures is limited, diamonds grow out of equilibrium. In this case, the atoms are not easy to diffuse, and the arrangement of the atoms producing the diamond is only short-range order, but the long-range arrangement contains a lot of defects and even a lot of impurities, so it is called drill-like carbon. Grow diamond or DLC by PVD method because the substrate temperature is very low, the growth rate is slow, usually only sink a thin layer. Because the film is thin, it can be attached to the surface of the complex workpiece. DLC film plating because the workpiece is not affected by high temperature, so the DLC PVD deposition is widely used, can be used for mold coating and hard disk protective film. To grow a thicker diamond film, the atoms must diffuse to a stable position in the crystal lattice, so the substrate temperature must rise, but not high enough to convert the resulting diamond into graphite.
十三、试说明CVD法生长钻石薄膜之特性?
Explain the properties of CVD diamond films?
为使CVD的钻石生长顺利，碳源常用已具钻石结构的甲烷。甲烷可视为以氢压出的单原子钻石。所以故煮饭时的煤气含大量悬浮的单原子钻石或DLC。甲烷分解时若氢原子可在附近若即若离的伴随，沉积出的碳可维持钻石的结构，并接合在钻石膜上而不同再转化成石墨。
Methane with a diamond-like structure is often used as a carbon source for the smooth growth of CVD diamonds. Methane can be thought of as a single atomic diamond pressed by hydrogen. So cooking gas contains a lot of suspended single atom diamonds or DLC. When methane is broken down, if hydrogen atoms can be found nearby, the carbon can be deposited to maintain the structure of the diamond, and then bonded to the diamond film and converted into graphite.
十四、使用CVD法成长钻石薄膜，氢元素和碳元素的浓度有何重要性?
What is the importance of hydrogen and carbon concentrations in growing diamond films by CVD method?
CVD生长钻石膜的瓶颈乃在避免碳氢化物形成石墨，因此氢原子应比碳源多很多。碳源浓度决定了钻石膜的生长速率，但碳源太高时氢原子会来不及维护钻石结构而使分解出的碳变成石墨。因此碳源太浓反而会降低转化成钻石的比率。碳源的浓度和温度决定了钻石随方向生长速率的差异，因此也决定了钻石的晶形。氢原子的浓度不仅决定了钻石膜是否能成长，也决定了钻石膜的质量。氢原子产生的比率不太受气体，但和温度有直接关联。随着热源温度的降低及距离的增大，氢原子的浓度也会急遽下降。
The bottleneck for CVD to grow diamond films is to prevent hydrocarbons from forming graphite, so there should be much more hydrogen than carbon sources. The concentration of the carbon source determines the growth rate of the diamond film, but when the carbon source is too high, the hydrogen atoms have too little time to maintain the structure of the diamond to turn the carbon into graphite. So too much carbon lowers the rate of conversion to diamonds. The concentration and temperature of the carbon source determine the difference in the rate of growth of the diamond in each direction, and therefore the crystal shape of the diamond. The concentration of hydrogen atoms determines not only whether the film can grow, but also its mass. The rate of hydrogen production is less dependent on gas, but is directly related to temperature. As the temperature of the heat source decreases and the distance increases, the concentration of hydrogen atom decreases rapidly.
十五、何为化学气相蒸镀(CVD)？主要的优缺点有哪些？
What is chemical vapor vapor deposition (CVD)? What are the main advantages and disadvantages?
化学气相蒸镀乃使用一种或多种气体，在一加热的固体基材上发生化学反应，并镀上一层固态薄膜。
Chemical vapor evaporation USES one or more gases to react on a heated solid substrate and to coat it with a solid film.
优点Advantages:
(1)真空度要求不高，甚至可以不需要真空，例如热喷覆
the vacuum is not required to be high, even without vacuum, such as hot spray
(2)沉积速率快，大气CVD可以达到1μm/min
the deposition rate is fast, and atmospheric CVD can reach 1μm/min
(3)与PVD比较的话。化学量论组成或合金的镀膜较容易达成
compared with PVD. The composition of chemical quantities or alloy coating is easier to achieve
(4)镀膜的成份多样化，如金属、非金属、半导体、光电材料、钻石薄膜等等
the composition of the coating is diversified, such as metal, non-metal, semiconductor, photoelectric material, diamond film and so on
(5)可以在复杂形状的基材镀膜，甚至渗入多孔的陶瓷
can be in the complex shape of the substrate coating, and even infiltration of porous ceramics
(6)厚度的均匀性良好，低压CVD甚至可以同时镀数十芯片
thickness uniformity is good, low - voltage CVD can even plating dozens of chips at the same time
缺点Disadvantages:
(1)热力学及化学反应机制不易了解或不甚了解
thermodynamics and chemical reaction mechanism are not easy or well understood
(2)需要在高温下进行，有些基材不能承受，甚至和镀膜产生作用
need to be carried out at high temperature, some base material can not bear, and even coating effect
(3)反应气体可能具腐蚀性、毒性或爆炸性，处理时需小心
the reaction gas may be corrosive, toxic or explosive, so care should be taken when handling
(4)反应生成物可能残余在镀膜上，成为杂质
the reaction products may remain on the coating and become impurities
(5)基材的遮蔽很难
it is difficult to cover the base material
十六、良好的薄膜须具备那些特性?影响的因素有那些?
What are the characteristics of a good film? What are the influencing factors?
通俗的定义为在正常状况下，其应用功能不会失效。想要达到这个目的，一般而言这层薄膜必须具有坚牢的附着力、很低的内应力、针孔密度很少、够强的机械性能、均匀的膜厚、以及足够的抗化学侵蚀性。薄膜的特性主要受到沉积过程、成膜条件、接口层的形成和基材的影响，随后的热处理亦扮演重要角色。
The popular definition is that under normal conditions, its application function will not fail. To achieve this, the film must generally have strong adhesion, low internal stress, low pinhole density, strong enough mechanical properties, uniform film thickness, and sufficient chemical resistance. The characteristics of the film are mainly influenced by the deposition process, film forming conditions, interface layer formation and substrate, and the subsequent heat treatment also plays an important role.
十七、沉积的薄膜有内应力的存在，其来源为何?
What are the sources of internal stresses in deposited films?
(1)薄膜和基材之间的晶格失配
lattice mismatch between thin film and substrate
(2)薄膜和基材之间的热膨胀系数差异
difference in thermal expansion coefficient between the film and the substrate
(3)晶界之间的互挤
intersqueezing between grain boundaries
十八、薄膜要有良好的附着力，必须具有哪些基本特性?
What are the essential properties of a thin film for good adhesion?
(1)接口层原子之间须有强的化学键结，最好是有化合物的形成或化学吸附，理吸附是不够的
there must be strong chemical bonds between the atoms in the interface layer, preferably the formation of compounds or chemical adsorption, which is not enough
(2)低的残存应力，这可能导因于镀膜和基材晶格或热膨胀系数的失配，也可能是薄膜本身存有杂质或不良结构
low residual stress, which may be due to the mismatch between the coating and the substrate lattice or thermal expansion coefficient, or the film itself has impurities or poor structure
(3)没有容易变形的表结构，如断层结构，具有机械粗糙的表面是可以减低问题的恶化
there is no surface structure that is easy to deform, such as fault structure. Mechanical rough surface can reduce the aggravation of the problem
(4)没有长期变质的问题，镀膜曝露在大气等的外在环境，如果本身没生氧化等化学反应，则镀膜自然失去其功能
there is no long-term deterioration problem. The coating is exposed to the external environment such as the atmosphere. If there is no chemical reaction such as oxidation, the coating will naturally lose its function
十九、膜厚的量测方法有哪些?
What are the measurement methods of film thickness?
大致上可分为原位量测、离位量测两类
It can be divided into two categories: in situ measurement and out of position measurement
原位星测系指镀膜进行中量测，普遍使用在物理气相沉积，如微天平、光学、电阻量测。
离位量测系指镀膜完成后量测，对电镀膜的行使较为普遍，具有了解电镀效率的目的，如质量、剖面计、扫描式电子显微镜。
In-situ star measurement refers to medium measurement of coating, which is commonly used in physical vapor deposition, such as microbalance, optical, and resistance measurement.
Off-site measurement refers to the measurement after the completion of the coating, which is common for electroplating and has the purpose of understanding the plating efficiency, such as mass, profile meter and scanning electron microscope.
二十、何为物理蒸镀?试简述其步骤?
What is physical evaporation? Describe the steps.
物理蒸镀就是把物质加热挥发，然后将其蒸气沉积在预定的基材上。由于蒸发源须加热挥发，又是在真空中进行，故亦称为热蒸镀或真空蒸镀。
Physical evaporation is the evaporation of material by heat, and then the vapor deposited on a predetermined substrate. Because the evaporation source must heat volatilization, is in the vacuum, so also known as hot evaporation or vacuum evaporation.
其可分为三个步骤It can be divided into three steps
(1)凝态的物质被加热挥发成汽相
the condensed material is heated and evaporated into vapor phase
(2)蒸汽在具空中移动一段距离至基材
the steam moves a distance to the substrate in a vacuum
(3)蒸汽在基材上冷却凝结成薄膜
the steam is cooled on the substrate and condensed into a film