The most \”trenched\” academician! He used platinum to repair automatic doors

In November 1977, the Institute of Semiconductors of the Chinese Academy of Sciences will \”carry out research on the main factors affecting the yield and reliability of large-scale integrated circuits, and develop high-performance chips for supercomputers\” \”High-quality, high-level integrated circuits\” are listed as major scientific research projects.

The comrades of the Institute of Semiconductor worked hard day and night. However, after a year of research, they encountered difficulties in producing a 4,000-bit MOS dynamic random access memory – the yield rate could not be improved and the progress was slow. .

At this time, a scientist came to the rescue. In less than a year, he not only solved the problem of developing large-scale integrated circuits, but also formulated scientific and strict production and R&D regulations. He is Wang Shouwu, one of the founders of China\’s semiconductor science, a semiconductor device physicist and an academician of the Chinese Academy of Sciences.

Academician Wang Shouwu Source丨Chinese Scientists Museum

In October 1978, Wang Shouwu took over the work under the unfavorable scientific research environment and began to be fully responsible for the development of 4,000-bit MOS dynamic random access memory, storming the yield rate. At that time, he proposed \”not only to develop successful samples, but also to have a certain yield.\”

Wang Shouwu first analyzed the reasons for the low yield, and then formulated targeted solutions.

When he first started, he encountered a thorny problem – the door of the air shower room at the entrance to the ultra-clean area was often broken.

According to requirements, each staff member must take a 40-second wind shower before entering the ultra-clean area. However, the quality of the air shower room doors at that time was not up to par, and they often broke down, leaving people locked in the air shower room.room, so someone changed the automatic control door to a manual switch. Although it is convenient for people to enter and exit, it is difficult to ensure that everyone can take a 40-second wind shower before entering the ultra-clean area.

Wang Shouwu requested that the automatic control door be repaired, but the repairmen in the electrician class were helpless. So he took matters into his own hands and repaired it. After analysis, Wang Shouwu found that the fault mainly occurred at the contact point of a relay because the contact material did not pass the test. So he thought of using platinum as the contact point material, because platinum has a high melting point and is not easily oxidized at high temperatures.

Sure enough, since Wang Shouwu welded two pieces of platinum on the contact points, the automatic door has never malfunctioned again.

Wang Shouwu worked in ultra-clean line in 1979 Source丨Institute of Semiconductors, Chinese Academy of Sciences

Wang Shouwu also insists on strict process inspection. He believes that only by inspecting every process, finding faults, and solving problems can the yield rate be improved. At the beginning, some workers were not used to strict operations, and Wang Shouwu did a lot of ideological work for this. At work, Wang Shouwu sets an example. He comes early and leaves late every day, and often stays in the ultra-clean line for several hours or even more than ten hours at a time.

Driven by his rigorous scientific research style, the atmosphere in the ultra-clean line has taken on a new look. Scientific researchers perform their duties and strictly control the work, and the workers operate seriously and meticulously. In the end, the research team\’s efforts achieved good results, and the yield of 4,000-bit N-channel MOS dynamic random access memory dies was finally significantly improved.

On September 28, 1979, my country successfully developed a 4,000-bit MOS dynamic random access memory, with a batch yield of more than 20% and up to 40%, the highest level in the country.

From October 1978 to September 1979, Wang Shouwu’s team produced a total of 104 samples of three layouts of large-scale integrated circuits. From October to November 1979, eight consecutive batches were officially put into production. 275 finished products were produced, with a die yield rate of more than 20%, and reliability testing was conducted.

The important breakthrough of the successful development of 4,000-bit MOS dynamic random access memory not only won the first prize of the Chinese Academy of Sciences Science and Technology Achievement Award in 1980, but more importantly, it ended my country\’s inability to manufacture large-scale integrated circuits. History!

Source丨Chinese Scientists Museum

The feeling of loving the motherland and serving the country runs through Wang Shouwu\’s life. Just like what he said in the school magazine \”People\’s Wisdom\” when he was 11 years old: \”Work hard to save the country, work hard to enrich the country, and work hard to strengthen the country.\”

Reference materials:

[1] Li Yanping, Kang Jing, Yin Xiaodong. Building Dreams with Silicon Cores: Biography of Wang Shouwu [M] China Science and Technology Press , 2015.1.

[2] The \”pioneer\” of China\’s semiconductor research – Wang Shouwu, a national model worker in 1979 and an academician of the Chinese Academy of Sciences [J]. Trade Union Expo, 2019, (24): 45- 48.

Source: Chinese Scientists Museum