Enhancing the strain limit of stretchable organic transistors by Schottky barrier-dominated transport mode

Abstract

Stretchable organic field-effect transistors (OFETs) are ideal candidates for wearable technologies, human-machine interfaces, soft robots and implantable devices, but they suffer from mechanical stress concentration, microcracks, and interfacial damage under large geometric variation, which leads to severe performance degradation. To transcend this limitation, we propose an O₂ plasma-assisted barrier regulation strategy for the fabrication of the organic source-gated transistor (OSGT). The Schottky barrier dominated transport mode of OSGTs substantially reduces the sensitivity of electrical performance to mechanical strain, thereby enhancing the strain limit of stretchable OFETs under geometric variations. The stretchable OSGTs could maintain a high on/off ratio (10⁶) at 300% strain and the performance has no obvious attenuation. This architectural strategy shifts the focus from material engineering to device design, offering broader prospects for the development of stretchable electronic devices requiring large deformations.

Balancing mechanical stretchability and performance is a challenge in flexible devices. Here, the authors develop a universal O₂ plasma-assisted barrier engineering strategy for stretchable organic source-gated transistors, theoretically decoupling electrical performance from strain and enhancing the strain limit.

Introduction

Stretchable electronics are promoting a surging demand in various applications owing to their mechanical adaptability and electrical performance^1–12. Notably, as the core element of stretchable electronic systems, stretchable organic field-effect transistors (OFETs) are highly attractive due to their light weight, low cost and capability for maintaining intimate tissue contact even with movement and size changes, making them ideal candidates for wearable technologies, human-machine interfaces, soft robots and implantable devices^13–21.

The development of high-performance stretchable OFETs fundamentally relies on polymer semiconductors that can preserve excellent charge transport properties under mechanical strain. Substantial research efforts have focused on designing intrinsically stretchable semiconductors through precision molecular engineering, which balances mechanical elasticity with charge transport efficiency by fine-tuning backbone flexibility, side-chain dynamics, and cross-linking density^22–26. Moreover, Bao’s group has demonstrated that polymer nanoconfinement can boost stretchability by orders of magnitude while completely preserving the original charge mobility characteristics^27–29. Despite these remarkable achievements, a critical challenge remains: current stretchable OFETs exhibit severe performance degradation at larger strain, primarily due to microstructural damage in the semiconductor layer under extreme deformation^30,31. This degradation stems from the operating mechanism of OFETs, which relies on efficient charge transport through continuous conjugated pathways in the organic semiconductor. Under large strain, molecular packing and π-π stacking are disrupted, leading to a reduction in charge carrier mobility and detrimental cracks that disrupt conduction paths. This limitation substantially constrains their application in scenarios requiring high deformability, such as dynamic tissue interfaces or highly stretchable electronic skins. Therefore, the balance between mechanical stretchability and device performance is an inherent contradiction of stretchable devices, which may need transistor with distinct working mode to enhance the limitation.

In this work, we propose a universal O₂ plasma-assisted barrier regulation strategy for the fabrication of the organic source-gated transistor (OSGT)^32–36. The device operates on the principle of a Schottky barrier dominated transporting mode, which effectively alleviates the strain limit of stretchable organic transistors. Owing to their source-dominated working mechanism, the stretchable OSGTs exhibit tolerance to geometric variations^37,38, maintaining an on/off ratio of 10⁶ even under a strain of 300%. Moreover, we have successfully obtained a stretchable current stabilizer that operates stably under the 300% stretching strain. By transcending the material-dependent limits of conventional stretchable OFETs, stretchable OSGTs greatly alleviate the inherent trade-off between the electrical performance and the stretchability without the need for material modification, and bring vitality to the development of stretchable electronics. Theoretically, the source-dominated mechanism could ensure stable operation under even larger strains. Our work not only provides a pathway to achieve high-performance stretchable electronics but also opens up broader possibilities for applications requiring robust and reliable operation under continuous mechanical strain.

Results and discussion

Electrical characterization of organic source-gated transistors

OFETs typically exhibit a low contact barrier, and the conducting channel is coupled to the gate electrode capacitance through an insulating medium. Therefore, the gate-source voltage (V_GS) controls the conductivity of the channel. Unlike OFETs, the source contact in the OSGT is replaced by a Schottky barrier similar to a diode^35,39,40. The OFET current is saturated only at high drain–source voltage (V_DS), whereas  the OSGT achieves saturation at significantly lower V_DS owing to complete depletion of the semiconductor layer by the Schottky source^41–44.

A key characteristic of the OSGT is the Schottky barrier at the source contact. P-type small molecule 2,9-didecyldinaphthol [2,3-b:2’,3’-f]thiophene (C₁₀-DNTT) is used as the active layer to construct bottom-gate top-contact (staggered) OSGTs, as shown in Fig. 1b. The OSC was then treated with O₂ plasma for different times (Fig. 1a), and the source and drain (Ag) were prepared by thermal evaporation. Based on this strategy, the Schottky barrier is introduced at the interface between the source and the OSC to construct OSGTs (Fig. 1c). Firstly, we conducted Atomic force microscope (AFM) characterization of the morphology and thickness of the C₁₀-DNTT film before and after O₂ plasma treatment (Supplementary Fig. 1). It was found that the morphology of the O₂ plasma treated C₁₀-DNTT film did not change. The thickness of the O₂ plasma treated C₁₀-DNTT film was consistent with the initial 20 nm, which proved that our O₂ plasma treatment method was mild. Moreover, the plasma-treated film maintained its morphological integrity even after 2.5 years of storage in ambient conditions (Supplementary Fig.2).

Fig. 1. Characterization of the organic source-gated transistors properties.

a Schematic of the O₂ plasma treatment process. b, c Structure and schematic illustration of Schottky barrier (Φ_SB) height in a C₁₀-DNTT-Ag OSGT with Schottky contacts (The dashed line shows the band bending of the C₁₀-DNTT without O₂ plasma treatment). d Output characteristics of the C₁₀-DNTT-Ag OFET (V_DS = − 60 V, V_GS = 0 to ‒60 V in ‒10 V steps, L = 200 μm, W = 1000 μm). e–g Output characteristics of the C₁₀-DNTT-Ag OSGT with the different O₂ plasma treatment time (V_DS = − 60 V, V_GS = 0 to ‒60 V in ‒10 V steps, L = 200 μm, W = 1000 μm). h Typical transfer characteristics of the C₁₀-DNTT-Ag OFET and the C₁₀-DNTT-Ag OSGT with different O₂ plasma treatment times (V_DS = − 60 V, L = 200 μm, W = 1000 μm). i P_sat of the C₁₀-DNTT-Ag OFET and the C₁₀-DNTT-Ag OSGT. j Typical transfer characteristics of the C₁₀-DNTT-Ag OFET and the C₁₀-DNTT-Ag OSGT with the different channel length (V_DS = − 30 V, L = 10, 30,50 and 100 μm, W = 1000 μm). k Bias stress effect tests of the C₁₀-DNTT-Ag OSGT and C₁₀-DNTT-Ag OFET (V_GS = − 60 V and V_DS = − 60 V).

When the OSC is not treated with O₂ plasma, the device exhibits typical OFET characteristics (Fig. 1d), the current reaches saturation only at high V_DS, and the on/off ratio reaches 10⁸ (Supplementary Fig. 3), with the threshold voltage (V_TH) approaching 0 V (Fig. 1h). To further evaluate the electrical impact of O₂ plasma treatment, we extracted the subthreshold swing (SS) from the transfer curves shown in Fig.1h. As summarized in Supplementary Fig.4, the SS increases only from ~3.00 V/dec (untreated OFET) to ~3.16 V/dec (60 s O₂ plasma-treated OSGT). This minor change indicates that the plasma treatment does not introduce a significant density of deep traps. This suggests that the plasma-induced modification primarily affects the source contact barrier rather than creating bulk or interface traps. With the increase of O₂ plasma treatment time, it can be found from the output curves (Fig. 1e–g) that the saturation voltage (V_sat) gradually decreases and the saturation current (I_sat) gradually flattens. As the treatment time increases, the V_sat decreases from the initial ‒60 V to ‒15 V at the V_GS of ‒60 V, while the on/off ratio does not change significantly. Notably, the resulting OSGT does not follow the OFET formula (V_sat = V_GS – V_TH), but low saturation voltage and flat saturation current are the basis of low operating voltage and low power consumption. According to the Eq. (1) (L is the channel length, W is the channel width), the saturation power density (P_sat) of the initial OFET device and OSGT device under different processing times is calculated (Fig. 1i).

$$P_{\mathrm{sat}}=\left(V_{\mathrm{sat}}\times I_{\mathrm{sat}}\right)/\left(L\times W\right)$$ 1

Compared with OFETs, the OSGT has a lower P_sat of 0.69 W cm⁻² because the OSGT has lower V_DS, which gives the OSGT a broad application prospect in stretchable wearable devices.

In recent years, OFETs have faced many problems, such as the inevitable short-channel effect with the reduction of device size^45–50, poor operational stability^51–54, and incompatibility between flexible device performance and stretchability^27,55–57. However, due to the unique working mechanism of OSGTs, the I_DS is mainly controlled by the source contact and barrier height, rather than by the channel in the traditional sense, which makes OSGT have many advantages over OFET. As shown in Fig. 1j, when the channel length is shortened to 30 µm and 10 µm, the V_TH of the OFET shifts significantly and the off-state current has a significant increase at the same time. However, when the channel size is reduced, there is no severe offset in the V_TH and off-state current of the OSGT device. At the same time, the OSGT obtained has good operational stability (Fig. 1k), the continuous bias stress over 8000 s was applied to the OFET and OSGT device. In striking contrast, the drain current of the OFET and OSGT remains at 38% and 96% of the initial value. To further assess long-term stability and to verify that the plasma treatment does not introduce charge-trapping centers, we extended the bias stress to 25,000 s under the same conditions. As shown in Supplementary Fig. 5, the OSGT retains 86% of its initial drain current after 25,000 s, with no significant shift in threshold voltage and no degradation in subthreshold swing. In contrast, the untreated OFET retains only 12% of its initial current and exhibits a large V_TH shift of approximately −15 V. These results demonstrate that the O₂ plasma treatment does not introduce a high density of charge-trapping centers, and that the Schottky-barrier-dominated transport mode provides long-term bias stability compared to the conventional OFET. Furthermore, we demonstrate the necessity of our O₂ plasma-assisted barrier regulation strategy for constructing OSGT devices by fabricating asymmetric electrodes (Supplementary Figs. 6–8). Firstly, the C₁₀-DNTT film was treated without O₂ plasma, and then the asymmetric electrode Au-Ag was prepared. The output curve showed typical OFET characteristics when Au or Ag was the source electrode and the other end was the drain electrode. When the C₁₀-DNTT film is treated with O₂ plasma at the optimal time, the output curve has obvious OSGT characteristics when the source electrode is Ag, while the output curve does not have the characteristic of saturation under low V_DS when the source electrode is Au. Therefore, the important characteristics of the source electrode in OSGT are verified. At the same time, we prepared the (5 nm Ag+15 nm Au)−20 nm Au asymmetric electrode device, and also found that OSGT was formed only when the C₁₀-DNTT film was treated by O₂ plasma and (5 nm Ag+15 nm Au) was the source electrode. However, it has also been verified that after O₂-plasma treatment of OSCs, only 5 nm Ag can form OSGT.

The mechanism of C₁₀-DNTT-Ag OSGT

The formation of a Schottky contact at the source electrode is the foundational condition for realizing OSGTs and establishing the Schottky barrier dominated transport mode crucial for enhancing the strain limit. In order to study the effective Schottky barrier (Φ_SB) of the OFET and OSGT, the transfer curves (Fig. 2a,d) and output curves (Supplementary Figs. 9–10) were measured in the temperature range of 320 K- 350 K. The Φ_SB was calculated using the thermionic emission model (Eq. 2)^58–61:

$$I_{\mathrm{DS}}=A{A}^{*}{T}^2\exp \left[-\frac{q{\varphi }_{\mathrm{SB}}}{k_{\mathrm{B}}T}\right]$$ 2

where A is the junction area, A^* is the equivalent Richardson constant, k_B refers to the Boltzmann constant, q stands for the elementary charge, I_DS represents the channel current between source and drain, and T is the absolute temperature. Figure 2b,e shows the Arrhenius plots of the OFET and OSGT device for ln(I_DS/T²) as a function of 1/T according the transfer curves, showing good linear relation at each gate voltage, indicating that the drain current is dominated by thermionic emission. As shown in Fig. 2c,f, the extracted flat-band Schottky barrier height of the C₁₀-DNTT-Ag OSGT (0.73 eV) is obviously higher than the C₁₀-DNTT-Ag OFET (0.31 eV). The increase in Φ_SB is attributed to the surface chemical modification induced by O₂ plasma treatment. As shown in Supplementary Fig. 11, X-ray photoelectron spectroscopy (XPS) measurements reveal the appearance of S–O bonds in the S2p spectrum after plasma treatment. Importantly, depth-profiling XPS demonstrates that these S–O species are only within the semiconductor surface and disappear after a mild sputter etch, leaving only the intrinsic S–C bonds of the pristine semiconductor. This confirms that the O₂ plasma treatment is strictly surface-localized and does not penetrate into the bulk. Consequently, the bulk π-π stacking and charge transport pathways remain intact. Furthermore, these S–O bonds remain chemically stable after storage of the plasma-treated film in ambient conditions for 10 days (Supplementary Fig. 12), and correspondingly the Φ_SB remains stable after one week of storage, with extracted values of 0.71 eV (fresh) and 0.70 eV (after one week) (Supplementary Fig. 13). This confirms that the surface modification is durable under practical device operation and storage.

Fig. 2. Mechanism of the C₁₀-DNTT-Ag OSGT.

a, d Temperature-dependent transfer characteristics of the C₁₀-DNTT-Ag OFET and C₁₀-DNTT-Ag OSGT. All transfer curves are obtained at V_DS = − 60 V, L = 200 μm, and W = 1000 μm. b, e Plots of ln (I_DS/T²) versus 1000/T under different V_GS extracted from (a, d). c, f Φ_SB of the C₁₀-DNTT-Ag OFET and C₁₀-DNTT-Ag OSGT as a function of V_GS. g Schematic diagram of the electrode changes. h Output characteristics of the C₁₀-DNTT-Ag OSGT and C₁₀-DNTT-Ag OFET with the different L_S/L_D ratio of the unchanged size of the source electrode (V_GS = − 60 V, L = 200 μm, and W = 1000 μm). i Output characteristics of the C₁₀-DNTT-Ag OSGT and C₁₀-DNTT-Ag OFET with the different L_D/L_S ratio of the unchanged size of the drain electrode. L_S: the length of the source. L_D: the length of the drain.

In an OSGT, most of the current passes through the front end of the source, and the current in the saturation regime can be written as Eq. 3³³

$$I_{\mathrm{sat}}=W\sqrt{\frac{q{N}_{\mathrm{C}}{C}_{\mathrm{G}}\left(V_{\mathrm{G}}-V_{\mathrm{TH}}\right)e^{-{\varphi }_{B,eff}/kT}}{H}}\times {\mu }_{\mathrm{n}}\left[\frac{C_{\mathrm{G}}}{C_{\mathrm{S}}+C_{\mathrm{G}}}\left(V_{\mathrm{G}}-V_{\mathrm{TH}}\right)+\frac{{\varphi }_B^0}{q}\right]$$ 3

where W is the source contact width, q is the fundamental charge, µ_n is the electron mobility in the semiconductor, N_C is the effective density of states in the conduction band, V_TH is the threshold voltage of the OSGT, k is the Boltzmann constant, T is the temperature, and C_S and C_G are the capacitance per unit area of the semiconductor and the capacitance per unit area of the gate insulator, respectively. According to the Eq. (3), the I_DS of the OSGT is not sensitive to the change of channel length and is only related to the width of the source electrode. Subsequently, we prepared a series of electrodes (E1-E6) to verify this characteristic of OSGT (Fig. 2g and Supplementary Fig. 14). For E1-E3 devices, the size of the source electrode is kept unchanged, and change the size of the drain electrode, so that the channel length is unchanged (200 µm), the length of the source (L_S) is 1000 µm and the length of the drain (L_D) is 1000 µm, 500 µm and 250 µm, respectively. As shown in Fig. 2h and Supplementary Figs. 15–16, for OFET devices, consistent with conventional behavior, the on-state current decreases regularly with the increase of the L_S/L_D ratio. For OSGT devices, the I_DS remained almost unchanged with the increase of the L_S/L_D ratio. For E4-E6 devices (Supplementary Fig. 14), keep the size of the drain electrode unchanged, change the size of the source electrode, so that the channel length is unchanged (200 µm), the L_D is 1000 µm and the L_S is 1000 µm, 500 µm and 250 µm, respectively. In this case, for OSGT devices and OFET devices (Fig. 2i and Supplementary Figs. 15–16), the I_DS all show a regular decrease as the ratio of L_D/L_S increases. Based on the above experimental phenomena, it is found that because of the unique source control mechanism of OSGT, changing the drain electrode will not affect the I_DS when the source electrode is kept unchanged, which makes OSGTs have greater tolerance to geometric variations, making it promising in the field of flexible electronics.

Preparation and electrical properties of stretchable OSGT and OSGT arrays

Based on the above results, we applied the OSGT with tolerance to geometric variations to the stretchable system and explored its potential in stretchable devices.

To confirm that the O₂ plasma treatment induces the same source-barrier effect in the polymer semiconductor indacenodithiophene-co-benzothiadiazole (IDTBT) as observed in C₁₀-DNTT, we performed parallel experiments on rigid IDTBT/Ag devices (Si/SiO₂ substrate) under identical plasma conditions. As shown in Supplementary Figs.S17–19, the treated IDTBT devices exhibit low-saturation output characteristics (Supplementary Fig.S17), source-controlled transport with I_DS independence of drain electrode length (Supplementary Figs.S18) and clear evidence of S–O species in XPS (Supplementary Fig.S19). These results confirm that the OSGT mechanism is fully transferable to the polymer semiconductor IDTBT, justifying its use in the stretchable devices described below.

Since we demonstrated the importance of Ag as the source electrode in the construction of OSGT, and we needed it to be compatible with stretchable devices, we prepared 5 nm Ag using thermal evaporation deposition based on the sprayed single-wall carbon nanotubes (SWCNTs) and then transferred it to the O₂ plasma treated IDTBT, as shown in Fig. 3a–b. The photographs of the stretchable OSGT in its initial state and under 300% strain are shown in Fig. 3c. The sheet resistance of three different electrodes, SWCNTs, evaporated Ag and Ag@SWCNTs, was tested (Supplementary Fig. 20). The Ag@SWCNTs showed a lower sheet resistance (6424 Ω sq⁻¹). Moreover, under the strain, the Ag@SWCNTs showed a small change in sheet resistance (ΔR/R_o) to prove its application potential in stretchable devices (Supplementary Fig. 21). The OSGT based on SWCNTs, evaporated Ag and Ag@SWCNTs were prepared. By exploring their electrical properties (Supplementary Fig. 22), it was found that electrodes based on SWCNTs and Ag@SWCNTs had similar properties. For devices obtained by evaporated Ag, the on-state current of the device has a severe decrease, the V_TH drift, and the sheet resistance of the evaporated Ag change greatly under the strain, which cannot meet the needs of stretchable devices.

Fig. 3. Intrinsically stretchable OSGTs with tolerance to geometric variations.

a Schematic of the stretchable OSGTs array structure. b Schematic diagram of the electrode/OSC structure. c Photographs of the device under 0% strain and 300% strain, as well as the stretching equipment diagram. d Typical transfer curves of the stretchable OFET stretched parallel to the charge transport direction under different strains (V_DS = − 60 V, L = 1000 μm, W = 4000 μm). e, f Typical transfer curves of the stretchable OSGT stretched parallel to and perpendicular to the charge transport direction under different strains (V_DS = − 60 V, L = 1000 μm, W = 4000 μm). g On/off ratio of the stretchable OSGT and OFET under different strains (50, 100, 200, 225, 250, 275 and 300%). h Comparison of previously reported intrinsically stretchable transistors with the stretchable OSGT in this work in terms of the on/off ratio and strain.

To explore the potential of OSGT as a device structure in stretchable systems, we fabricated fully stretchable OSGTs in a top-contact and bottom-gate structure with Ag@SWCNTs electrodes, IDTBT stretchable semiconductor, and a styrene-ethylene-butylene-styrene (SEBS) dielectric. Similarly, we also obtained the stretchable OSGT with optimal performance by adjusting the O₂ plasma treatment time. The output characteristic (Supplementary Fig. 23) curves show that when the IDTBT film was not treated with O₂ plasma, it exhibited  clear stretchable OFET characteristics, and I_DS increased with the increase of V_DS. However, under the optimal O₂ plasma treatment time, I_DS saturated at lower V_DS, and it is found that the on/off ratio and V_TH of the device have no obvious changes after the O₂ plasma treatment through the transfer characteristic curves (Supplementary Fig. 24). To further confirm the formation of a Schottky-barrier-dominated transport mode, we performed temperature-dependent electrical measurements on stretchable IDTBT/Ag-SWCNT/SEBS OSGT and stretchable IDTBT/Ag-SWCNT/SEBS OFET (Supplementary Fig. 25). The results clearly demonstrate that the Φ_SB of stretchable OSGT (0.93 eV) is obviously higher than that of the stretchable OFET (0.63 eV). This significant increase provides direct evidence that the O₂ plasma treatment effectively introduces a high Φ_SB, thereby enabling the source-gated transistor operation in IDTBT.

When the stretchable OFET was stretched parallel to the charge transport direction, the transfer characteristic curves in Fig. 3d that the on-state current (Supplementary Fig. 26) and on/off ratio (Fig. 3g) decreased greatly and V_TH drifted with the increase of the strain. The on/off ratio changed from the initial 10⁸ to 10³ under 300% tensile strain. This shows that for stretchable OFET devices, there is a natural incompatibility between the electrical properties of the device and the stretchability. For stretchable OSGT devices, when stretched parallel to the charge transport direction and perpendicular to the charge transport direction (Fig. 3e–f), the electrical performance of the devices decreases less with the increase of the tensile strain, and the on-state current (Supplementary Fig. 26) of the devices changes relatively little, even under the tensile strain of up to 300%, the on/off ratio can be as high as 10⁶ (Fig. 3g). To quantitatively verify that the source barrier remains the dominant resistance component under strain, we performed transfer length method (TLM) measurements on stretchable IDTBT OSGTs. As detailed in Supplementary Figs.27–28, the R_c·W is consistently significantly higher than the R_ch·W. Even at 300% strain, due to geometric and morphological changes, both R_c·W and R_ch·W increased substantially, but R_c·W remained larger than R_ch·W. This quantitatively indicates that the source barrier is always the limiting factor for current throughout the entire tensile range. Consequently, the OSGT maintains a competitive on/off ratio of 10⁶ under 300% strain compared to previously reported stretchable transistors (Fig. 3h and Supplementary Table1). We believe that owing to the unique working mechanism, the OSGT can theoretically maintain stable electrical properties under greater tensile strain.

The mechanical reliability and low-voltage capability of individual stretchable OSGTs are further demonstrated in Supplementary Figs.29–31. The device operates at a low voltage of −10 V with clear transistor characteristics, confirming that its low saturation voltage enables practical low-voltage operation. We also examined the recovery behavior by comparing the transfer characteristics before stretching (initial), after release from 100% strain, and after release from 300% strain (Supplementary Fig.30). After release from 100% strain, the device retains nearly identical transistor characteristics to the initial state, demonstrating that the OSGT mechanism is highly robust under moderate deformation and fully recovers. After release from 300% strain, the device still exhibits clear gate modulation and a distinguishable on/off ratio, but some degradation in on-current and a slight shift in threshold voltage are observed. This irreversible degradation likely originates from morphological damage to the polymer semiconductor or interfaces under extreme strain, rather than from a failure of the source-dominated transport mechanism. Cyclic stretching at 25% strain for 10,000 cycles causes only moderate on-current variation, showing mechanical robustness under repeated loading. These results extend the evaluation from quasi-static stretching to low-voltage, recovery, and cyclic conditions.

Based on the above experimental results, we verified that the OSGT device has good tolerance to geometric variations. Then, we prepared a set of patterns with unchanged source electrodes and various shapes of drain electrodes (Supplementary Fig. 32). The electrical properties of this set of devices are similar, and the on-state current and the on/off ratio are almost unchanged. This provides the ability to control the electrical properties of the profiled electrode devices.

Subsequently, we connected the stretchable OSGT and OFET in series with the OLEDs to visualize their stretchability at tensile strains of 100, 200 and 300% (Fig. 4a–b). For the stretchable OFET, the device performance decays rapidly at the strain up to 300%, ultimately making it difficult to drive the OLED properly. For the stretchable OSGT, when the tensile strain is increased to 300%, the light intensity is slightly reduced, far exceeding the OFET device drive OLED light intensity at 300% tensile strain.

Fig. 4. Stretchable OSGTs applications.

a Photographs of the stretchable device under different strains. b Photographs of OLEDs driven by stretchable OSGTs and OFETs under different strains. c Supply V_DS with voltage fluctuation of 30 V (‒30 to ‒60 V) and the output drain current (I_DS) of the stretchable OFET and the stretchable OSGT as a function of time. d Photographs of stretchable OSGTs arrays under pressing, (e) under twisting and (f) under poking. g On-state current of stretchable OSGTs under various conditions.

Then we prepared a current stabilizer based on the stretchable OSGT (Supplementary Fig. 33a), which avoids the influence of input voltage fluctuations on output current changes. Even under the fluctuating input voltage of ‒30 V, ‒40 V and ‒60 V, stretchable OSGT can have a stable output current compared with OFET because of its flat saturation current (Fig. 4c). When the strain of the stretchable OSGT reaches 300%, the stretchable OSGT still maintains a stable and constant output current, which indicates the successful preparation of the stretchable current stabilizer. At the same time, we series OLED in the current stabilizer circuit, and the series OLED has a relatively stable light intensity (170.6 nW, 174.8 nW, 172.9 nW) under different input voltages, as shown in Supplementary Fig. 33b. The current stabilizer based on the OSGT has a simpler circuit structure, and has a good application prospect.

For the demonstration, 10 × 10 stretchable OSGT arrays with a bottom-gate/top-contact (BG/TC) structure were fabricated (Supplementary Fig. 34). The patterned organic semiconductor in the array is achieved by high power O₂ plasma etching, and the patterned semiconductor array is shown in Supplementary Fig. 35. The stretchable OSGT can be prepared by transferring all the stretchable functional layers onto the SEBS substrate, where the patterned organic semiconductor is treated with O₂ plasma. To evaluate the output uniformity across the array, we measured the output characteristics of all 100 devices. As shown in Supplementary Fig.36, every device exhibits the characteristic low-voltage saturation behavior of OSGTs. The extracted V_sat are all within –15 V, with a narrow distribution (Supplementary Fig.37). This confirms that the mild O₂ plasma process provides good saturation voltage uniformity. We then examined the transfer characteristics to assess the uniformity of V_TH and on-state current. As shown in Supplementary Fig.38, all the stretchable OSGTs performed well. The values of the V_TH and on-state current of the 100 OSGTs in the array are mapped as shown in Supplementary Fig. 39 and the results show that the OSGTs in the array exhibited low performance variability. To verify the OSGT array’s capability for tolerance to geometric variations, the fully stretchable OSGT array was subjected to various mechanical deformations, including pressing, twisting, and poking with pointed objects (Fig. 4d–f). Notably, the stretchable OSGT array showed no severe decrease in electrical properties, confirming its excellent tolerance to geometric variations (Fig. 4g).

We further evaluated the array-level performance under tensile strain. As shown in Supplementary Fig.40, the stretchable OSGT array maintains clear gate modulation up to 300% strain in both stretching directions, and its actual on/off ratio does not show significant attenuation. Finally, to demonstrate operation under dynamic deformation relevant to wearable electronics, the array was attached onto a finger and the drain current was monitored during repeated finger motion. As shown in Supplementary Fig.41, the device exhibits repeatable on/off switching, confirming its applicability under body-motion conditions.

Despite these advantages for stretchable and low-frequency wearable applications, it is important to acknowledge the inherent trade-offs of the OSGT architecture. While the high source barrier inevitably reduces the on-current and limits the high-frequency operation (e.g., MHz-range switching or RF circuits), it simultaneously provides low saturation voltage, flat output characteristics, and high strain tolerance. Therefore, the stretchable OSGTs are best suited for low-speed, low-power, and high-stability applications such as wearable biomedical sensors, human-machine interfaces, and soft robotic skins. For potential high-speed flexible circuits, hybrid integration with conventional OFETs could be explored in future work.

In conclusion, this work breaks through the traditional material-centric paradigm and establishes OSGTs with a Schottky-barrier-dominated transport mode. As a result, the degradation of electrical performance under mechanical strain is significantly suppressed compared with conventional OFETs, demonstrating a reduced strain sensitivity that enhances the practical strain limit of stretchable organic devices. The source-dominated mechanism enables stretchable OSGTs to exhibit low saturation voltage, low power consumption, good bias stress stability, and high tolerance to both geometric variations and short-channel effects. Under 300% tensile strain, it still has an on/off ratio of 10⁶, and the device performance has no obvious attenuation. Furthermore, we have achieved a stretchable current stabilizer, which can maintain a stable and constant output current when the tensile strain reaches 300%. This strategy opens up a development dimension for the application of stretchable electronics in intelligent sensing, stretchable organic integrated circuits, human-interactive wearable systems and other fields.

Methods

Materials and instruments

C₁₀-DNTT was purchased from Sigma-Aldrich. Polymer semiconductor IDTBT was purchased from Solarmer Beijing Inc. Elastomer SEBS was supplied by Asahi Kasei company, with SEBS H1062 specifically employed as the elastomer substrate and SEBS H1052 utilized as the dielectric layer in the fabrication of stretchable OFETs and OSGTs. The dispersed SWCNTs solution for electrodes was purchased from Chengdu Zhongke Times Nanomaterials Co., Ltd. The electrical characterizations of OFETs and OSGTs were performed by an Agilent B1500A and a PDA FS380 with the assistance of a probe station system in dark conditions. The atomic force microscope (AFM) was measured by Bruker Dimension ICON-PT in the air. Optical images were measured by VK-X1050 3D laser confocal microscopy. The X-ray photoelectron spectroscopy (XPS) was performed by PHI 5000 Versaprobe.

Device fabrication and characterization

The OFETs and OSGTs were fabricated on silicon substrates. The substrates consist of a highly doped Si wafer (gate electrode) and a 300 nm thermally oxidized SiO₂ layer (dielectric layer). Then, the Si wafers were modified with OTS in a vacuum oven for 1 h at 120 °C. The C₁₀-DNTT film (20 nm) was deposited by vacuum thermal evaporation at 0.05 Å s⁻¹ under 10⁻⁴ Pa. The C₁₀-DNTT film was then treated with O₂ plasma using a Diener Femto-SLS system (power range 0–100 W). The optimized treatment conditions were: RF power = 30 W, chamber pressure = 0.38 mbar, O₂ flow rate = 40 sccm, duration = 60 s, at room temperature. Subsequently, Ag electrodes (20 nm) were thermally deposited onto the substrate as the source and drain electrodes in a vacuum at a rate of 0.1 Å s⁻¹.

All stretchable functional layers were prefabricated on the Si/SiO₂ wafers substrates and transferred layer by layer onto SEBS substrate to prepare stretchable OSGTs and OFETs. The substrate layers were prepared on the Si/SiO₂ wafers by dropping the SEBS-H1062 solution (200 mg/ml in toluene), followed by annealing at 40 °C for 5 h. The gate electrodes were fabricated by spray-coating SWCNTs using a spray gun. The SEBS solution(H1052, 60 mg/ml in toluene) was spin-coated on the OTS-treated Si/SiO₂ surface at 1000 r.p.m., to form a stretchable dielectric film. IDTBT was dissolved in anhydrous chlorobenzene (5 mg mL⁻¹, 60 °C, 12 h). The IDTBT film was prepared on an OTS-treated Si/SiO₂ substrate using the solution shearing method (0.51 mm/s at 70 °C). Then, the semiconductor film was baked on a hot plate (120 °C) for 10 min in a nitrogen atmosphere to remove the residual solvent. After the transfer, the semiconductor film of the stretchable OSGT was treated with O₂ plasma under the same conditions (Diener Femto-SLS, 30 W, 0.38 mbar, 40 sccm, 60 s, room temperature). The source and drain (S/D) electrodes were fabricated by spray-coating SWCNTs using a spray gun through a metal mask plate. After that, 5 nm-thick Ag electrode was thermally evaporated (0.1 Å s⁻¹) to form SWCNT@Ag electrodes for stretchable OSGT.

Author contributions

Y.F. and X.Z. performed the experiments. Y.F., X.Z., X.C., H.Y., L.Q.L. and L.L. wrote the manuscript. S.W., S.S., Y.W., Z.W. and Y.H. assisted in the experiments. X.C., L.Q.L., H.Y., and L.L. conceived and supervised this work. W.H. provided valuable suggestions on this work. All authors contributed to the discussion of the paper.

Peer review

Peer review information

Nature Communications thanks Jin Young Oh, and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. A peer review file is available.

Funding

This work was supported by the National Natural Science Foundation of China (52225304 to L.Q.L., 52473193 to X.C., 52403243 to Y.H., 52502048 to L.L., 52121002, 92577206, T2441002, and U21A6002 to W.H.) and Natural Science Foundation of Tianjin City (25JCYBJC00140 to L.L.).

Data availability

All data supporting this study and its findings are available within the article and its Supplementary Information. The data corresponding to this study are available from the first author and the corresponding authors upon request. Source data are provided in this paper. Source data are provided with this paper.

Competing interests

The authors declare no competing interests.

Supplementary information

The online version contains supplementary material available at 10.1038/s41467-026-75302-3.