Thickness-Dependent Study of Infrared-Visible Compatible Stealth in Transparent Conductive Thin Films

doi:10.16553/j.cnki.issn1000-985x.2025.0052

Abstract

Abstract: The indium tin oxide （ITO） transparent conductive thin films were prepared by DC magnetron sputtering. The relationship between film thickness and optoelectronic properties was investigated. Structural modulation of ITO thin films was performed to analyze carrier concentration and mobility. Special emphasis was placed on examining the influence of film thickness on infrared wavelength reflectivity. By setting specific sputtering power， substrate temperature， and atmosphere to control the thickness of ITO thin films， films with a thickness of 100~500 nm were obtained， and the preparation of ITO thin films with preferred （400） orientation， high infrared reflectivity， and high visible transmittance was achieved. The special film thickness constructed constitutes a synergistic carrier concentration and mobility， which mitigates part of the effect of diffuse reflection， and the films exhibit unique interfacial properties and energy states under the condition of a film thickness of 400 nm， and an average visible transmittance of 89.51% is obtained to achieve an average infrared reflectance of 97.37% in a wide spectral band of 2.5~15 μm. And the resulting film quality factor is as high as 815.19×10^-4 Ω^-1， which is significantly better than that of the reported transparent conductive thin film system， solving the problem of visible light and infrared-compatible stealth， and providing a new way of thinking for the preparation of spectrum-compatible optical stealth materials and smart windows.

Key words: indium tin oxide thin film; DC magnetron sputtering; infrared stealth; thickness; optical property; Hall parameter

CLC Number:

YANG Jiwei, DONG Ling, GU Dong, XU Huarui, ZHAO Yunyun, YANG Tao, LI Haiping, LI Jie, ZHU Guisheng. Thickness-Dependent Study of Infrared-Visible Compatible Stealth in Transparent Conductive Thin Films[J]. Journal of Synthetic Crystals, 2025, 54(9): 1614-1621.

Figures/Tables 9

References 22

[1]	QI D， WANG X， CHENG Y Z， et al. Design and characterization of one-dimensional photonic crystals based on ZnS/Ge for infrared-visible compatible stealth applications［J］. Optical Materials， 2016， 62： 52-56.
[2]	QUAN C， GU S， LIU P， et al. Spectrally selective radiation infrared stealth based on a simple Mo/Ge bilayer metafilm［J］. Optics and Lasers in Engineering， 2024， 180： 108328.
[3]	RENTERIA E J， HEILEMAN G D， NEELY J P， et al. Infrared-transparent semiconductor membranes for electromagnetic interference shielding of millimeter waves［J］. Advanced Materials Technologies， 2024， 9（19）： 2401013.
[4]	WU J J， WANG K X， WEI C， et al. Ideal photothermal materials based on Ge subwavelength structure［J］. Molecules， 2024， 29（21）： 5008.
[5]	GAO Z Q， FAN Q， TIAN X X， et al. An optically transparent broadband metamaterial absorber for radar-infrared bi-stealth［J］. Optical Materials， 2021， 112： 110793.
[6]	LIU S J， ZHU F J， HUANG J G， et al. Fast inverse design of microwave and infrared bi-stealth metamaterials based on equivalent circuit model［J］. Journal of Applied Physics， 2024， 136（11）： 113106.
[7]	ASHOK P， CHAUHAN Y S， VERMA A. High infrared reflectance modulation in VO₂ films synthesized on glass and ITO coated glass substrates using atmospheric oxidation of vanadium［J］. Optical Materials， 2020， 110： 110438.
[8]	XIA C T， JI R， JIANG S M， et al. Enhanced electroluminescence from silicon-based light-emitting devices with Mg_0.4Zn_0.6O/erbium-doped ZnO heterostructures by using ITO/MoO₃ combined anode［J］. Applied Surface Science， 2025， 682： 161782.
[9]	QI Y H， LI N， QI G， et al. First-principles studies of the Al， Ga， in-doped ZnO defect formation energy［J］. Applied Physics， 2016， 6（2）： 15-21.
[10]	WANG K Z， JIAO P W， CHENG Y Y， et al. ITO films with different preferred orientations prepared by DC magnetron sputtering［J］. Optical Materials， 2022， 134： 113040.
[11]	高嘉乐. 粗糙度对高温目标红外辐射偏振特性的影响研究［J］. 传感器技术与应用， 2024， 12（3）： 286-297.
	GAO J L. A study of the effect of roughness on the polarization characteristics of infrared radiation from a high-temperature objective［J］. Journal of Sensor Technology and Application， 2024， 12（3）： 286-297 （in Chinese）.
[12]	SCHLICK C. An inexpensive BRDF model for physically-based rendering［J］. Computer Graphics Forum， 1994， 13（3）： 233-246.
[13]	ISHIDA T， KOBAYASHI H， NAKATO Y. Structures and properties of electron-beam-evaporated indium tin oxide films as studied by X-ray photoelectron spectroscopy and work-function measurements［J］. Journal of Applied Physics， 1993， 73（9）： 4344-4350.
[14]	HE K D， YANG X L， YAN H， et al. Surface properties of indium tin oxide treated by Cl₂ inductively coupled plasma［J］. Applied Surface Science， 2014， 316： 214-221.
[15]	GOSWAMI S， SHARMA A K. Wide tuning of epsilon-near-zero plasmon resonance in pulsed laser deposited ITO thin films［J］. Journal of Applied Physics， 2023， 134（16）： 163106.
[16]	XU Y， WAN G P， MA L L， et al. Indium tin oxide as a dual-band compatible stealth material with low infrared emissivity and strong microwave absorption［J］. Journal of Materials Chemistry C， 2023， 11（5）： 1754-1763.
[17]	KANAIZUKA K， YAMAGUCHI M. Construction of ITO nanoparticle immobilized substrates and evaluation of their photocurrent responses［J］. ECS Meeting Abstracts， 2024， MA2024-02（59）： 3997.
[18]	杨　涛，陈彩明，黄瑜佳，等. ITO/AgNWs/ITO薄膜的制备及其性能研究［J］. 人工晶体学报， 2024， 53（7）： 1150-1159.
	YANG T， CHEN C M， HUANG Y J， et al. Preparation and properties of ITO/AgNWs/ITO films［J］. Journal of Synthetic Crystals， 2024， 53（7）： 1150-1159 （in Chinese）.
[19]	CHEN Q L， GONG T， CHEN W C， et al. Rapid annealing obtained ITO films with both extremely low infrared emissivity and high visible light transmission for energy-efficient window applications［J］. Ceramics International， 2025， 51（3）： 3163-3169.
[20]	BANDHU H， ASHOK P， VERMA A. Active and passive infrared emittance tuning using optically transparent unpatterned ITO thin films［J］. Optical Materials， 2024， 157： 116181.
[21]	DONG L， CHEN Y D， ZHU G S， et al. Highly （400） preferential ITO thin film prepared by DC sputtering with excellent conductivity and infrared reflectivity［J］. Materials Letters， 2020， 260： 126735.
[22]	DONG L， ZHU G S， XU H R， et al. Fabrication of nanopillar crystalline ITO thin films with high transmittance and IR reflectance by RF magnetron sputtering［J］. Materials， 2019， 12（6）： 958.

Sample	Thickness/nm	Sheet resistance/（Ω·□^-1）	UV-visible transmittance （400~800 nm）/%	Infrared reflectance （2 500~16 000 nm）/%	Resistivity/（10^-4 Ω·cm）	Carrier concentration/（10²⁰ cm^-3）	Hall mobility/（cm²·V^-1·s^-1）
1	100	30	91.45	81.95	4.69	7.54	17.70
2	200	9.8	93.14	92.28	2.94	9.83	21.60
3	300	7.73	91.97	95.50	2.71	9.11	25.30
4	400	4.05	89.51	97.37	1.62	16.5	23.30
5	500	3.62	85.51	96.30	1.81	16.8	20.60

Sample	Thickness/nm	Sheet resistance/（Ω·□^-1）	UV-visible transmittance （400~800 nm）/%	Infrared reflectance （2 500~16 000 nm）/%	Resistivity/（10^-4 Ω·cm）	Carrier concentration/（10²⁰ cm^-3）	Hall mobility/（cm²·V^-1·s^-1）
1	100	30	91.45	81.95	4.69	7.54	17.70
2	200	9.8	93.14	92.28	2.94	9.83	21.60
3	300	7.73	91.97	95.50	2.71	9.11	25.30
4	400	4.05	89.51	97.37	1.62	16.5	23.30
5	500	3.62	85.51	96.30	1.81	16.8	20.60

Electrode thickness/nm	Resistivity/（10^-4 Ω·cm）	UV-visible transmittance （400~800 nm）/%	Infrared reflectance （2 500~15 000 nm）/%	FOM/（10^-4 Ω^-1）	Ref.
ITO-100	1.94	86.42	86.00	128.34	［19］
PET/ITO-250	5.08	75.20	70.21	19.27	［20］
PET/ITO-660	9.71	66.50	80.00	11.27	［20］
ITO-908	1.384	88.34	86.37	600.01	［21］
ITO-584	2.6	87.10	75.00	286.21	［10］
ITO-1031	1.44	88.49	89.18	—	［22］
ITO-400	1.62	89.51	97.37	815.19	This work

Electrode thickness/nm	Resistivity/（10^-4 Ω·cm）	UV-visible transmittance （400~800 nm）/%	Infrared reflectance （2 500~15 000 nm）/%	FOM/（10^-4 Ω^-1）	Ref.
ITO-100	1.94	86.42	86.00	128.34	［19］
PET/ITO-250	5.08	75.20	70.21	19.27	［20］
PET/ITO-660	9.71	66.50	80.00	11.27	［20］
ITO-908	1.384	88.34	86.37	600.01	［21］
ITO-584	2.6	87.10	75.00	286.21	［10］
ITO-1031	1.44	88.49	89.18	—	［22］
ITO-400	1.62	89.51	97.37	815.19	This work