CN-122028659-A - Semiconductor device and method for manufacturing the same

CN122028659ACN 122028659 ACN122028659 ACN 122028659ACN-122028659-A

Abstract

The invention provides a semiconductor device and a preparation method thereof, wherein the preparation method of the semiconductor device comprises the steps of providing a semiconductor substrate, forming a target grid structure on the semiconductor substrate, forming a photoresist layer on the semiconductor substrate, photoetching the photoresist layer by utilizing a photomask to form a patterned photoresist layer, wherein the photomask comprises a light-transmitting region formed by a light-transmitting substrate, a light-shielding region formed by the light-transmitting substrate and a light-shielding layer covered on the light-transmitting substrate and a light-semi-transmitting region formed by the light-transmitting substrate and a light-semi-transmitting layer covered on the light-shielding layer, the heights of the light-transmitting region, the light-shielding region and the patterned photoresist layer corresponding to the light-semi-transmitting region are different, the patterned photoresist layer is provided with a stepped opening, the target grid structure is positioned in the stepped opening, and performing ion implantation on the semiconductor substrate by utilizing the patterned photoresist layer to form an ion implantation region. The invention can improve shadow effect in ion implantation process, and reduce probability of punching photoresist layer, and has larger process window.

Inventors

Request for anonymity

Assignees

青岛澳柯玛云联信息技术有限公司

Dates

Publication Date: 20260512
Application Date: 20241108

Claims (10)

1. A method of manufacturing a semiconductor device, comprising: Providing a semiconductor substrate, and forming a target gate structure on the semiconductor substrate, wherein two sides of the target gate structure are used for forming an ion implantation region; Forming a photoresist layer on the semiconductor substrate, wherein the photoresist layer covers the target gate structure; Photoetching the photoresist layer by using a photomask to form a patterned photoresist layer, wherein the photomask comprises a light transmission area, a light shielding area and a semi-transparent area, the light transmission area is formed by a light transmission substrate, the light shielding area is formed by the light transmission substrate and a light shielding layer covered on the light transmission substrate, the semi-transparent area is formed by the light transmission substrate and a semi-transparent layer covered on the light transmission substrate, the heights of the patterned photoresist layer corresponding to the light transmission area, the light shielding area and the semi-transparent area are different, the patterned photoresist layer is provided with a stepped opening, and the target grid structure is positioned in the stepped opening; and performing ion implantation on the semiconductor substrate by utilizing the patterned photoresist layer to form an ion implantation region.
2. The method of manufacturing a semiconductor device according to claim 1, wherein the semi-transmissive region is located between the light-shielding region and the light-transmissive region.
3. The method of manufacturing a semiconductor device according to claim 1, wherein the patterned photoresist layer corresponding to the semi-transmissive region has a lower height than the patterned photoresist layer corresponding to the light-shielding region, and the patterned photoresist layer corresponding to the semi-transmissive region is adjusted by adjusting a material of the semi-transmissive layer.
4. The method of manufacturing a semiconductor device according to claim 1, wherein the stepped opening includes a first opening and a second opening, the second opening being located above and in communication with the first opening, a cross-sectional width of the second opening being greater than a cross-sectional width of the first opening, the target gate structure being located in the first opening.
5. The method of manufacturing a semiconductor device according to claim 4, wherein the longer the length of the semi-transparent region is, the wider the cross section of the second opening is, and the greater the distance between the patterned photoresist layer corresponding to the light shielding region and the target gate structure is.
6. The method of manufacturing a semiconductor device according to claim 1, wherein the method of forming a photomask comprises: Providing a light-transmitting substrate; Forming a light shielding material layer on the light-transmitting substrate, and patterning the light shielding material layer to form a light shielding layer; Forming a semi-transparent material layer on the transparent substrate with the light shielding layer, and patterning the semi-transparent material layer to form a semi-transparent layer, wherein the semi-transparent layer on the transparent substrate is adjacent to the light shielding layer.
7. The method of manufacturing a semiconductor device according to claim 6, wherein the semi-transparent layer further extends to cover at least part of the light shielding layer.
8. The method according to claim 1, wherein the material of the light-transmitting substrate comprises glass or quartz, and/or the material of the light-shielding layer comprises chromium, and/or the material of the semi-light-transmitting layer comprises chromium oxide, silicon nitride, chromium cobalt, and molybdenum silicide.
9. The method of manufacturing a semiconductor device according to claim 1, wherein the semiconductor substrate is further formed with other gate structures spaced apart from the target gate structure, and the photoresist layer further covers the other gate structures when the photoresist layer is formed on the semiconductor substrate.
10. A semiconductor device, characterized in that it is manufactured by the manufacturing method of the semiconductor device according to any one of claims 1 to 9.

Description

Semiconductor device and method for manufacturing the same Technical Field The present invention relates to the field of integrated circuit fabrication, and more particularly, to semiconductor devices and methods of fabricating the same. Background Currently, logic core devices (Logic Core Device) in the industry suppress short channel effects of devices by Pocket Implant (PKT), and can adjust the PKT dose to achieve different threshold voltages (Vt), but when the PKT dose is too heavy, junction leakage is aggravated (Iboffworse), so the PKT tilt angle is typically increased to reduce the dose, and junction leakage is further improved (Iboff). However, in the case of gate structures closer to the photoresist layer (PR), shadow effect (shadowing effect) may cause large deviations in the actual implant volume and requirements of the PKT, resulting in lower Vt of the device. Shadow effect is generally improved by two methods, one is to improve the shadow effect by reducing the thickness of the photoresist layer, but the reduction of the thickness of the photoresist layer may cause the PKT to puncture the photoresist layer, and the other is to improve the shadow effect by increasing the distance from the gate structure to the photoresist layer, but the distance which can be increased is usually limited and the process window is small. Disclosure of Invention The invention aims to provide a semiconductor device and a preparation method thereof, which are used for improving shadow effect in an ion implantation process. To achieve the above and other related objects, the present invention provides a method of manufacturing a semiconductor device, comprising: Providing a semiconductor substrate, and forming a target gate structure on the semiconductor substrate, wherein two sides of the target gate structure are used for forming an ion implantation region; Forming a photoresist layer on the semiconductor substrate, wherein the photoresist layer covers the target gate structure; Photoetching the photoresist layer by using a photomask to form a patterned photoresist layer, wherein the photomask comprises a light transmission area, a light shielding area and a semi-transparent area, the light transmission area is formed by a light transmission substrate, the light shielding area is formed by the light transmission substrate and a light shielding layer covered on the light transmission substrate, the semi-transparent area is formed by the light transmission substrate and a semi-transparent layer covered on the light transmission substrate, the heights of the patterned photoresist layer corresponding to the light transmission area, the light shielding area and the semi-transparent area are different, the patterned photoresist layer is provided with a stepped opening, and the target grid structure is positioned in the stepped opening; and performing ion implantation on the semiconductor substrate by utilizing the patterned photoresist layer to form an ion implantation region. Optionally, in the method for manufacturing a semiconductor device, the semi-transparent region is located between the light shielding region and the light transmitting region. Optionally, in the method for manufacturing a semiconductor device, the height of the patterned photoresist layer corresponding to the semi-transparent region is lower than the height of the patterned photoresist layer corresponding to the light shielding region, and the height of the patterned photoresist layer corresponding to the semi-transparent region is adjusted by adjusting the material of the semi-transparent layer. Optionally, in the method for manufacturing a semiconductor device, the step-shaped opening includes a first opening and a second opening, the second opening is located above and in communication with the first opening, a cross-sectional width of the second opening is greater than a cross-sectional width of the first opening, and the target gate structure is located in the first opening. Optionally, in the method for manufacturing a semiconductor device, the longer the length of the semi-transparent region, the wider the cross section of the second opening, and the larger the distance between the patterned photoresist layer corresponding to the light shielding region and the target gate structure. Optionally, in the method for manufacturing a semiconductor device, the method for forming a photomask includes: Providing a light-transmitting substrate; Forming a light shielding material layer on the light-transmitting substrate, and patterning the light shielding material layer to form a light shielding layer; Forming a semi-transparent material layer on the transparent substrate with the light shielding layer, and patterning the semi-transparent material layer to form a semi-transparent layer, wherein the semi-transparent layer on the transparent substrate is adjacent to the light shielding layer. Optionally, in the method for manufacturing a semiconductor d