Semiconductor Packages: Rigorous Reliability Tests guide

Reliability Tests and Standards for Semiconductor Packages

This series covered the semiconductor back-end process, including semiconductor package types, packaging processes, and materials. In the final installment, we’ll discuss semiconductor package reliability tests and standards. This article will discuss how these standards are set and how semiconductor packages’ expected lifetime, reliability in various conditions, and mechanical reliability are tested.

Definition: Product Reliability

The quality of a semiconductor product depends on its compliance with standards and properties. Meanwhile, Semiconductor Packages device reliability is the probability that it will maintain its quality without failure over a set time, increasing customer satisfaction and repeat purchases. In this case, failures are product use errors, while defects are manufacturing or inspection errors. Therefore, a product is poor quality if it has many defects and unreliable if it fails frequently or while under warranty.

To elaborate, reliability is a system, part, or material’s ability to maintain quality and performance over time, distance, or use. This must be done without failure under particular usage or environmental conditions. Before mass production, Semiconductor Packages companies must ensure their quality and reliability meet industry standards. During mass production, these levels should be checked regularly.

Predefining reliability standards is crucial to assessing product reliability. A 100-product shipping company must consider the following questions: How many products should work after three years? What product operation time patterns are visible? Can 90 out of 100 products be guaranteed to work after five years? How long will 95/100 products work?

Testing is needed to verify standards. Although it would be ideal to test a product’s reliability for three, five, or even longer years at these stages, doing so would delay mass production. Therefore, companies test reliability using accelerated testing and statistics. Using reliability functions, lifetime distributions, and average lifetime, reliability validation can be completed quickly.

Standard JEDEC

Semiconductor manufacturers test their products and report the results. Customers can use the results to decide if the product meets their needs or assess its reliability. If a Semiconductor Packages company and its customers have different evaluation criteria, they must align their standards. To meet company and customer needs, semiconductor companies usually follow JEDEC standards.

Product Lifetime Reliability Tests

In addition to international evaluation standards, many metrics assess product reliability. These include semiconductor product lifetime assessments.

Early Failure Rate

The early failure rate (EFR) estimates user device failures within a year. Some product lines can reduce this period to six months or increase it to over a year, depending on the system’s lifetime or reliability needs.

Operating Life at High and Low Temperatures

Product lifetime evaluations often use the high temperature operating life (HTOL) test. It evaluates temperature and voltage stress issues during product operation. The comprehensive HTOL test detects premature, accident, and wear-and-tear failures.

Operating Life at High and Low Temperatures

Product lifetime evaluations often use the high temperature operating life (HTOL) test. It evaluates temperature and voltage stress issues during product operation. The comprehensive HTOL test detects premature, accident, and wear-and-tear failures.

Thermal Cycle

A thermal cycle (TC) tests a product’s tolerance to instantaneous temperature changes in different user environments. Stress-induced fatigue failures can occur in semiconductor packages and modules made of materials with different CTEs.

Temperature Humidity Temperature Humidity Bias Storage Tests

The temperature humidity storage (THS) test evaluates Semiconductor Packages product tolerance in high humidity and temperatures. After opening the moisture-proof package, measure moisture absorption to simulate the user environment and determine the exposure time.

Pressure Cooker Test

The pressure cooker test (PCT), more rigorous than THS and THB, is ideal for early moisture resistance testing. Autoclave8 tests a plastic mold compound’s moisture resistance and mold structure reliability by infiltrating moisture with 100% relative humidity and high pressure.

Unbiased High Accelerated Stress, Life, and Stress Tests

UHAST stresses thin substrate-type Semiconductor Packages like fine-pitch ball grid array (FBGA) packages like a PCT to assess reliability. They also share failure identification and discovery skills.

Mechanical Factor Reliability Testing

Mechanical, climatic, and electrical factors stress semiconductor products during handling, storage, transportation, and operation. These loads significantly impact equipment design reliability.