熱壓成型廣泛運用於拋棄式微流體晶片的製作中，過程中因為加工溫差的變化導致熱塑性基材翹曲的疑慮，此翹曲行為對於晶片後續結合的品質影響相當大，因此本研究運用熱壓成型實驗與平面度誤差的計算，來觀察晶片翹曲所造成的平面度誤差對於實際晶片結合品質的影響。過程中，我們設計及製造了五種不同的四吋模具，每一個模具上皆有不同的微結構，會影響壓克力材料在熱壓後有不同的翹曲，進而利用這些不同平面度誤差的晶片進行實驗來了解翹曲對於晶片結合的影響。為了量化晶片結合的品質，將結合後的晶片進行洩漏測試(leakage Test)與結合強度壓力測試(Burst Pressure Test)。實驗結果顯示，平面度誤差(平均14.5μm，標準差4.3μm)較小的晶片可以有較強的結合強度(7.58 bars)；而平面度誤差較高的晶片(平均18.3μm ，標準差3.7μm) 及 (平均23.2μm，標準差4.8μm)僅能承受2至3 bars，且結合成功率較低。因此，從實驗結果可以歸納出晶片的翹曲行為是影響結合品質的關鍵因素，且會影響後續晶片的結合品質與強度。

Warpage is a common problem in the injection molding, rolling printing, and hot embossing of thermoplastic microfluidic chips. Warpage can greatly reduce bond quality and can even lead to chip failure. This study adopted an experimental methodology to investigate the influence of warpage on bonding quality. We created thermoplastic microfluidic chips with different degrees of warpage, by using a micromilling machine to fabricate five 4 inches brass mold inserts with various micro features. The micro features were used to vary the embossing pressure and thereby induce warpage of various degrees. The warped microfluidic chips, (25mm in width and 35mm in length, ) were bonded to pristine PMMA substrates using solvent. The bonded chips were subjected to leakage tests and burst pressure tests in order to characterize bond quality. Our experiment results clearly showed that chips with smaller warpage, (14.5μm with a STD of 4.3μm), could withstand burst pressure of 7.58 bars with 100% bonding success. The chips with larger warpage, (18.3μm with a STD of 3.7μm) and (23.2μm with a STD of 4.8μm, ) were able to withstand burst pressure of only 2 to 3 bars and presented a only 33% likelihood of forming a successful bond. In this study, warpage was shown to be a crucial factor in bonding quality, and wherein a pronounced warpage deteriorated bonding strength and reduced the likelihood of bonding successfully to the substrate to form thermoplastic microfluidic chips.

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