Stress control in trench field-plate power MOSFETs and its impact on on-resistance reduction

The limitations regarding lateral cell pitch narrowing and on-resistance reduction were investigated. Trench field plate MOSFETs feature deep trenches with thick oxide films. This disrupts the stress balance, leading to significant wafer warpage, which poses a critical challenge in device integratio...

Full description

Saved in:
Bibliographic Details
Main Authors: Hiroaki Kato, Shin-ichi Nishizawa, Wataru Saito
Format: Article
Language:English
Published: Elsevier 2025-06-01
Series:Power Electronic Devices and Components
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S277237042500015X
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849329778952241152
author Hiroaki Kato
Shin-ichi Nishizawa
Wataru Saito
author_facet Hiroaki Kato
Shin-ichi Nishizawa
Wataru Saito
author_sort Hiroaki Kato
collection DOAJ
description The limitations regarding lateral cell pitch narrowing and on-resistance reduction were investigated. Trench field plate MOSFETs feature deep trenches with thick oxide films. This disrupts the stress balance, leading to significant wafer warpage, which poses a critical challenge in device integration. Stress control has become essential for enabling cell pitch narrowing, achieving high breakdown voltage device designs, and implementing innovative device pattern layouts such as dot pattern cell structures. In this study, stress and wafer warpage associated with lateral cell pitch narrowing were estimated using 3D simulations. Based on these results, the on-resistance reduction limit was also estimated through analytical models. For stripe pattern cell structures, pitch narrowing was constrained by both increased wafer warpage and on-resistance saturation. Notably, the X-direction wafer warpage was identified as the limiting factor for pitch narrowing in high breakdown voltage device designs. In contrast, the dot pattern cell structure significantly reduced wafer warpage and allowed narrower pitches compared to the stripe pattern, despite a weakened mobility enhancement effect.
format Article
id doaj-art-1c00fbd483654b85a7ddffd5a764b119
institution Kabale University
issn 2772-3704
language English
publishDate 2025-06-01
publisher Elsevier
record_format Article
series Power Electronic Devices and Components
spelling doaj-art-1c00fbd483654b85a7ddffd5a764b1192025-08-20T03:47:10ZengElsevierPower Electronic Devices and Components2772-37042025-06-011110009010.1016/j.pedc.2025.100090Stress control in trench field-plate power MOSFETs and its impact on on-resistance reductionHiroaki Kato0Shin-ichi Nishizawa1Wataru Saito2Interdisciplinary Graduate School of Engineering Science, Kyushu University, Fukuoka, 816-8580 Japan; Corresponding author.Research Institute for Applied Mechanics, Kyushu University, Fukuoka, 816-8580 JapanResearch Institute for Applied Mechanics, Kyushu University, Fukuoka, 816-8580 JapanThe limitations regarding lateral cell pitch narrowing and on-resistance reduction were investigated. Trench field plate MOSFETs feature deep trenches with thick oxide films. This disrupts the stress balance, leading to significant wafer warpage, which poses a critical challenge in device integration. Stress control has become essential for enabling cell pitch narrowing, achieving high breakdown voltage device designs, and implementing innovative device pattern layouts such as dot pattern cell structures. In this study, stress and wafer warpage associated with lateral cell pitch narrowing were estimated using 3D simulations. Based on these results, the on-resistance reduction limit was also estimated through analytical models. For stripe pattern cell structures, pitch narrowing was constrained by both increased wafer warpage and on-resistance saturation. Notably, the X-direction wafer warpage was identified as the limiting factor for pitch narrowing in high breakdown voltage device designs. In contrast, the dot pattern cell structure significantly reduced wafer warpage and allowed narrower pitches compared to the stripe pattern, despite a weakened mobility enhancement effect.http://www.sciencedirect.com/science/article/pii/S277237042500015XMOSFETStrainPiezo effectDot cellStripe cellWafer warpage
spellingShingle Hiroaki Kato
Shin-ichi Nishizawa
Wataru Saito
Stress control in trench field-plate power MOSFETs and its impact on on-resistance reduction
Power Electronic Devices and Components
MOSFET
Strain
Piezo effect
Dot cell
Stripe cell
Wafer warpage
title Stress control in trench field-plate power MOSFETs and its impact on on-resistance reduction
title_full Stress control in trench field-plate power MOSFETs and its impact on on-resistance reduction
title_fullStr Stress control in trench field-plate power MOSFETs and its impact on on-resistance reduction
title_full_unstemmed Stress control in trench field-plate power MOSFETs and its impact on on-resistance reduction
title_short Stress control in trench field-plate power MOSFETs and its impact on on-resistance reduction
title_sort stress control in trench field plate power mosfets and its impact on on resistance reduction
topic MOSFET
Strain
Piezo effect
Dot cell
Stripe cell
Wafer warpage
url http://www.sciencedirect.com/science/article/pii/S277237042500015X
work_keys_str_mv AT hiroakikato stresscontrolintrenchfieldplatepowermosfetsanditsimpactononresistancereduction
AT shinichinishizawa stresscontrolintrenchfieldplatepowermosfetsanditsimpactononresistancereduction
AT watarusaito stresscontrolintrenchfieldplatepowermosfetsanditsimpactononresistancereduction