Preparation method of drain electrode lightly-offset structure

Abstract

The invention provides a preparation method of a drain electrode lightly-offset structure. The preparation method comprises the steps of glass substrate crystallization, P-Si substrate imaging, gate insulation layer film formation and gate layer film formation. The drain electrode lightly-offset structure is formed through the following steps of a gumming step, a half-tone exposure step, a developing step, a first-time metal etching step, a first-time ion implantation step, a photoresist-ashing step, a second-time metal etching step, a demoulding step and a second-time ion implantation step, wherein photoresist is subjected to half-tone exposure and developing, and two times of heavily doped and lightly doped ion implantation steps, the photoresist-ashing step and the two times of metal etching steps are combined, so that a source electrode or drain electrode heavily doped region, a gate lightly doped region and a drain electrode lightly doped region are formed, a drain electrode lightly offset (LDO) structure is formed, a hot carrier effect is effectively relieved, a leakage current is reduced, the drain electrode lightly-doped structure has an easy-to-control size and better processing repeatability and uniformity, the production cost and the bad product rate are reduced, and the reliability of a TFT (Thin Film Transistor) product is improved.

Description

technical field [0001] The invention relates to the field of semiconductor device preparation and display, in particular to a preparation method of a light drain offset structure. Background technique [0002] In the display industry, the leakage characteristics of thin film crystalline silicon (Thin Film Transistor, referred to as TFT) have always been the characteristics that enterprises and R&D personnel pay attention to. If the leakage current of thin film transistor TFT is too large, it will not be able to play a good role in the switching of thin film transistor TFT. characteristic. When the thin film transistor TFT is turned off, a large current still flows. The reason for the leakage current of thin film transistor TFT is mainly the hot carrier effect, especially the high mobility polysilicon Poly-Si, microcrystalline silicon and single crystal silicon-thin film transistor TFT, in the node part with different doping concentration, A large leakage current will be ge...

AI Technical Summary

Problems solved by technology

In this preparation method, the gate layer Gate is used for over-etching. After the gate layer Gate is over-etched, the extra size on both sides is used as the size of the drain lightly doped LDD structure. However, th

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