TFT-LCD制造流程及光学规格介绍--080527

1、P.1 TFT-LCD模组模组結構組成結構組成 TFT-LCD工作原理工作原理 TFT-LCD製作流程簡介製作流程簡介 TFT-LCD光學規格介紹光學規格介紹P.2Thin Film Transistor Liquid Crystal Display薄膜電晶體液晶顯示器薄膜電晶體液晶顯示器 The thin-film transistor liquid crystal display (TFT-LCD) is a cutting-edge display, which screens picture information by adjusting the amount of light pe

2、rmitted. TFT is a circuit formed with semiconductor films on a thin glass substrate to control liquid crystals. This circuit plays a vital role in controlling each pixel, the basic unit of a picture image. The color filter displays a color image by coating the pixel (red, green and blue) on a glass

3、substrate. P.3 Driver ICCellTFT-LCD panelBacklightFront viewBack viewX-PCBLamp ConnectorDriver ICTiming ControllerSignal InterfaceY-PCBLVDS receiverTFT-LCD模组模组結構組成結構組成P.4P.5P.6关于液晶关于液晶 18881888年，澳大利亚植物学者莱尼茨尔（年，澳大利亚植物学者莱尼茨尔（ReinitzerReinitzer）研）研究胆甾醇在植物中的作用时，用胆甾基苯进行试验，无意究胆甾醇在植物中的作用时，用胆甾基苯进行试验，无意间发现了液

4、晶，但液晶的实际应用直到二十世纪五十年代间发现了液晶，但液晶的实际应用直到二十世纪五十年代才开始。才开始。 顾名思义，液晶是固液态之间的一种中间类状态。顾名思义，液晶是固液态之间的一种中间类状态。 液晶是一种有机化合物，在一定的温度范围内，它既具有液晶是一种有机化合物，在一定的温度范围内，它既具有液体的流动性、粘度、形变等机械性质，又具有晶体的热液体的流动性、粘度、形变等机械性质，又具有晶体的热（热效应）、光（光学各向异性）、电（电光效应）、磁（热效应）、光（光学各向异性）、电（电光效应）、磁（磁光效应）等物理性质。（磁光效应）等物理性质。 光线穿透液晶的路径由构成它光线穿透液晶的路径由构成它

5、的分子排列所决定。人们发现给液晶充电会改变它的分子的分子排列所决定。人们发现给液晶充电会改变它的分子排列，继而造成光线的扭曲或折射。排列，继而造成光线的扭曲或折射。 液晶按照分子结构排列的不同，分为三种：晶体颗粒粘液晶按照分子结构排列的不同，分为三种：晶体颗粒粘土状的称为近晶相（土状的称为近晶相（SmecticSmectic）液晶、类似细火柴棒的称为）液晶、类似细火柴棒的称为向列相（向列相（NematicNematic）液晶、类似胆固醇状的称为胆甾相）液晶、类似胆固醇状的称为胆甾相（CholesticCholestic）液晶。这三种液晶的物理特性都不尽相同，）液晶。这三种液晶的物理特性都不尽相

6、同，用于液晶显示器的是第二类的向列相（用于液晶显示器的是第二类的向列相（NematicNematic）液晶）液晶 P.7P.8TFT-LCD工作原理工作原理 P.9TFT-LCD工作原理工作原理 液晶是一种有机复合物，由长棒状的分子构成。在自然状液晶是一种有机复合物，由长棒状的分子构成。在自然状态下，这些棒状分子的长轴大致平行。态下，这些棒状分子的长轴大致平行。LCDLCD第一个特点是必须将第一个特点是必须将液晶灌入两个列有细槽的平面之间才能正常工作。这两个平面上液晶灌入两个列有细槽的平面之间才能正常工作。这两个平面上的槽互相垂直的槽互相垂直(90(90度相交度相交) )，也就是说，若一个平面

7、上的分子南北，也就是说，若一个平面上的分子南北向排列，则另一平面上的分子东西向排列，而位于两个平面之间向排列，则另一平面上的分子东西向排列，而位于两个平面之间的分子被强迫进入一种的分子被强迫进入一种9090度扭转的状态。由于光线顺着分子的排度扭转的状态。由于光线顺着分子的排列方向传播，所以光线经过液晶时也被扭转列方向传播，所以光线经过液晶时也被扭转9090度。但当液晶上加度。但当液晶上加一个电压时，分子便会重新垂直排列，使光线能直射出去，而不一个电压时，分子便会重新垂直排列，使光线能直射出去，而不发生任何扭转。发生任何扭转。LCDLCD的第二个特点是它依赖极化滤光片和光线本的第二个特点是它依赖

8、极化滤光片和光线本身，自然光线是朝四面八方随机发散的，极化滤光片实际是一系身，自然光线是朝四面八方随机发散的，极化滤光片实际是一系列越来越细的平行线。这些线形成一张网，阻断不与这些线平行列越来越细的平行线。这些线形成一张网，阻断不与这些线平行的所有光线，极化滤光片的线正好与第一个垂直，所以能完全阻的所有光线，极化滤光片的线正好与第一个垂直，所以能完全阻断那些已经极化的光线。断那些已经极化的光线。 只有两个滤光片的线完全平行，或者只有两个滤光片的线完全平行，或者光线本身已扭转到与第二个极化滤光片相匹配，光线才得以穿透。光线本身已扭转到与第二个极化滤光片相匹配，光线才得以穿透。LCDLCD正是由这

9、样两个相互垂直的极化滤光片构成，所以在正常情正是由这样两个相互垂直的极化滤光片构成，所以在正常情况下应该阻断所有试图穿透的光线。但是，由于两个滤光片之间况下应该阻断所有试图穿透的光线。但是，由于两个滤光片之间充满了扭曲液晶，所以在光线穿出第一个滤光片后，会被液晶分充满了扭曲液晶，所以在光线穿出第一个滤光片后，会被液晶分子扭转子扭转9090度，最后从第二个滤光片中穿出。另一方面，若为液晶度，最后从第二个滤光片中穿出。另一方面，若为液晶加一个电压，分子又会重新排列并完全平行，使光线不再扭转，加一个电压，分子又会重新排列并完全平行，使光线不再扭转，所以正好被第二个滤光片挡住。总之，加电将光线阻断，不

10、加电所以正好被第二个滤光片挡住。总之，加电将光线阻断，不加电则使光线射出。当然，也可以改变则使光线射出。当然，也可以改变LCDLCD中的液晶排列，使光线在中的液晶排列，使光线在加电时射出，而不加电时被阻断。但由于液晶屏幕几乎总是亮着加电时射出，而不加电时被阻断。但由于液晶屏幕几乎总是亮着的，所以只有的，所以只有 加电将光线阻断加电将光线阻断 的方案才能达到最省电的目的。的方案才能达到最省电的目的。 P.10TFT-LCD工作原理工作原理P.11TFT-LCD工作原理工作原理P.12TFT-LCD製作流程製作流程P.13 TFT-LCD製作流程製作流程TFT Process P.14 TFT-L

11、CD製作流程製作流程TFT Process P.15TFT-LCD製作流程製作流程TFT Process P.16process and processing steps are quite similar to that of the semiconductor industry. Deposition, photolithography and etching steps are common to both industries. The key differences are that the TFT is built on a glass substrate instead of a

12、 silicon wafer. In addition, the TFT requires a processing temperature ranging from approximately 300 to 500? compared to about 1,000?required for semiconductor fabrication. 1. PECVD (Plasma Enhanced Chemical Vapor Deposition) Process Before gas enters the chamber, the state of the vacuum is maintai

13、ned and the glass plate is heated to a specific temperature. When gas flows into the chamber, the RF voltage is applied from electrodes inside the chamber, which transform gas into a plasma state. From this plasma, precursors are formed and deposited on the glass substrate. 2. Sputtering Process Spu

14、ttering is the process wherein the gas ion, which is the high energy inside the plasma created by RF power or DC power collides with the target surface, resulting in the deposition of the target material on the plate. Generally, the target materials are mounted on the negative electrode surface. The

15、n, the sputtered target materials are deposited on the plate, which is put on the positive electrode. For sputtering, inactive gases are used, such as helium and argon, so that deposition material chemistry is not affected. P.173. Photolithography Process Photolithography is the transfer of a patter

16、n from the photo mask onto a substrate. The photolithography process begins when the substrate is coated with an extremely thin liquid film of photosensitive material, called photoresis. The light then exposes the photoresist, some of which is destroyed when exposed to the light. The unnecessary por

17、tion of the material is then cleaned from the surface through another process, leaving an extremely fine pattern behind. Another layer of the photoresist is then deposited to the substrate, exposed, cleaned, until all the layers have been printed or imaged onto the surface. The photolithography proc

18、ess is a critical step within the LCD manufacturing process because panel quality depends on the entire pattern formation. As such, it is extremely sensitive to particles and other forms of contamination. Thus, this process requires a special clean environment, commonly referred to as a clean room,

19、and precise control of equipment, chemicals and materials. In the future, this will prove increasingly important as advanced displays that offer greater functionality and higher performance will require increasingly complex and stringent manufacturing capabilities. 4. Dry etch Process The dry etch p

20、rocess uses reactive species, such as atoms or radicals from the gas plasma, to etch away a portion of the object material. When these species react with the material located on the plate, the open region of material transforms into a volatile state and is removed from the matrix. In this process, t

21、he reaction velocity is fast and fine patterns can be formed uniformly.P.18TFT-LCD製作流程製作流程Color Filter Process P.19TFT-LCD製作流程製作流程Cell Process P.20LCD production process can be described as follows:(1) the orientation layer on the lower and upper plate is formed;(2) the layer is properly positioned

22、so that the liquid crystal can properly align; (3) the spacer is dispensed, the seal is printed, and the two plates are assembled; (4) the liquid crystal is injected into the cell through the capillary effect; and (5) the injection hole is sealed.1. Printing the Orientation Layer The orientation lay

23、er is evenly spread on the pixel area of the upper and lower plate. The polyimide is spread on the drum thinly and evenly and is coated on the rubber plate, which has been patterned in advance. In turn, the polyimide is printed on the upper color filter or the lower TFT-array plate. After printing,

24、the polyimide is hardened through the process of annealing. 2. Rubbing Rubbing is the process that forms the straight groove on the hardened polyimide in a fixed direction in order to make the liquid crystal orient in a fixed direction. The straight groove can be formed by rubbing the panel in a cer

25、tain direction with the rubbing velvet attached to the rotating drum. P.21 3. Dispensing SpacersThe spacers are dispensed evenly in order to secure the fixed cell gap when assembling the upper and lower plate. After the spacers are mixed in the liquid with the proper concentration, they are then tra

26、nsported to the spray nozzle through the pump, and subsequently sprayed on the surface of the plate from the nozzle with high pressure. Heating dries the liquid, and the density of the spacer is adjusted between 100 ea/ and 200 ea/ according to the display size. The spacer shape is like a ball with

27、a diameter size between 4 and 5 which determines the cell gap between the plates. 4. Injecting the Liquid Crystal The liquid crystal is injected between the upper and lower plate using capillary action and pressure differences after the upper and lower plate are assembled. The process system consist

28、s of a vacuum pump, vacuum chamber, an up/down moving device, a jig, which contains the liquid crystal, and, an N system. At first, the internal cell vacuum level is maintained at about 10-3 Torr from the original vacuum state. The liquid crystal is then pulled into the cell by the capillary effect.

29、 When the cell is filled with liquid crystal up to about 80 percent , N?s then purged into the vacuum chamber slowly and the liquid crystal fills the remaining space in the cell as a result of the difference in pressure from inside and outside the cell. P.22TFT-LCD製作流程製作流程Module Process The module p

30、rocess is the step that determines the final quality of the product to be delivered to the customer. The step is completed once the polarizer, the drive IC, PCB, backlight unit and the frame are assembled. P.2310mm10mm10mm10mm1/4 H1/2 H3/4 H1/4 V1/2 V3/4 VY1Y11Y5Y4Y2Y12Y13Y8Y7Y6Y3Y9Y10a. 規格條件：(1)中心點

31、 (2)五點平均b. 影響亮度的因素 (1) Cell穿透率(开口率) (2) Gamma Curve (3) BL發光效率 (4) 燈管電流P.24 Luminance of all pixels White(L255)Luminance of all pixels Dark(L0)L255(or L63)L0CR=P.25 LCD的最大分辨率就是它的真实分辨率，也就是最佳分辨率。P.26CR10 (W/B) 液晶显示器的可视角度包括水平可视角度和垂直可视角度两个指标液晶显示器的可视角度包括水平可视角度和垂直可视角度两个指标：水平可视角度表示以显示器的垂直法线水平可视角度表示以显示器的垂直法

32、线( (即显示器正中间的垂直假想即显示器正中间的垂直假想线线) )为准，在垂直于法线左方或右方一定角度的位置上仍然能够正常的为准，在垂直于法线左方或右方一定角度的位置上仍然能够正常的看见显示图像，这个角度范围就是液晶显示器的水平可视角度；同样如看见显示图像，这个角度范围就是液晶显示器的水平可视角度；同样如果以水平法线为准，上下的可视角度就称为垂直可视角度。一般而言，果以水平法线为准，上下的可视角度就称为垂直可视角度。一般而言，可视角度是以对比度变化为参照标准的。当观察角度加大时，该位置看可视角度是以对比度变化为参照标准的。当观察角度加大时，该位置看到的显示图像的对比度会下降，而当角度加大到一定

33、程度，对比度下降到的显示图像的对比度会下降，而当角度加大到一定程度，对比度下降到到101101时，这个角度就是该液晶显示器的最大可视角。一般主流时，这个角度就是该液晶显示器的最大可视角。一般主流LCDLCD的的可视角度为可视角度为120160120160度。比较理想的可视角度应在度。比较理想的可视角度应在175175度以上（水平度以上（水平).).P.27 带宽是指每秒钟扫描过的图像点的个数，以带宽是指每秒钟扫描过的图像点的个数，以MHz(MHz(兆赫兹兆赫兹) )为单位，表明了显示器电路可以处理的频率范围。为单位，表明了显示器电路可以处理的频率范围。让我们举例说明。比如，在标准让我们举例说明。比如，在标准VGAVGA方式下，如果刷新频率为方式下，如果刷新频率为60Hz60Hz，则需要的带宽为，则需要的带宽为640640480480606018.4MHz18.4MHz；在；在10241024768768的分的分辨率下，若刷新频率为辨率下，若刷新频率为70Hz70Hz，则需要的带宽为，则需要的带宽为55.1MHz55.1MHz。以上的数。以上的数据是理论值，实际所需的带宽要高一些。据是理论值，实际所需的带宽要高一些。早期的显示器是固定频率的，现在的多频显示器采用自动跟踪早期的显示器是固定频率的，现在的多频显示器采用自动跟踪技术，使显示器的扫描频率自动与显示卡的输出同步，从而实现了技