Transistor array substrate fabrication for an LCD
A fabrication process for transistor array substrates of different sizes on a common substrate provides quality control, yield, and space efficiency advantages. In particular, a four-mask process, including a mask with diffraction slits, may be employed to fabricate transistors that share common channel characteristics for each of the transistor array substrates.
1. A fabrication method for multiple LCD panel models from transistor array substrates formed on a common substrate, the method comprising the steps of:
selecting areas on the common substrate where switching array substrates of different sizes will be formed;
fabricating switching devices using a common set of masks for each of the switching array substrates;
forming an alignment layer on each of the transistor array substrates;
forming a seal pattern around each of the transistor array substrates;
scattering spacers onto each transistor array substrate;
attaching the common substrate on which the switching devices are formed to a color filter substrate to form an LCD display panel;
cutting the LCD display panel into individual LCD panel models; and
disposing liquid crystal in each of the panel models through a liquid crystal injecting hole.
2. The method of claim 1 , wherein the switching devices are thin film transistors.
3. The method of claim 1 , wherein the step of fabricating comprises the step of fabricating through a four mask process that includes a diffraction slit mask.
4. The method of claim 3 , wherein the slit mask includes a ‘U’-shaped channel slit-pattern.
5. The method of claim 3 , wherein the slit mask comprises a ‘U’-shaped source forming pattern, a bar-shaped drain forming pattern, and a channel slit-pattern between the source forming pattern and the drain forming pattern.
6. The method of claim 1 , wherein the step of fabricating switching devices comprises:
forming a gate electrode on the common substrate;
forming a gate insulating layer;
forming an active layer on the gate insulating layer;
forming source and drain electrodes on the active layer;
forming a passivation layer on the common substrate; and
forming pixel electrodes connected to the drain electrodes.
7. The method of claim 1 , further comprising the step of sealing the liquid crystal injecting hole.
8. A fabrication method for multiple transistor array substrates on a common substrate for multiple LCD panel models, the method comprising the steps of:
selecting areas on the common substrate where switching array substrates of different sizes will be formed;
fabricating the switching devices for each switching array substrate, regardless of size, through a multiple-mask process that applies the same masks for each switching array substrate.
9. The method of claim 8 , where the step of forming the switching devices comprises the steps of:
fabricating gate lines on each switching array substrate;
forming a gate insulating layer for insulating the gate lines;
forming an active layer on the gate insulating layer;
forming source and drain electrodes on the active layer;
forming a passivation layer on the common substrate; and
forming a pixel electrode on the passivation layer.
10. The method of claim 8 , where the switching device is a thin film transistor.